Answer:
(6, 4 )
Step-by-step explanation:
Given the 2 equations
2x - 10y = - 28 → (1)
- 10x + 10y = - 20 → (2)
Adding (1) and (2) term by term eliminates the term in y, that is
- 8x = - 48 ( divide both sides by - 8 )
x = 6
Substitute x = 6 into either of the 2 equations and evaluate for y
Substituting into (1)
2(6) - 10y = - 28
12 - 10y = - 28 ( subtract 12 from both sides )
- 10y = - 40 ( divide both sides by - 10 )
y = 4
Solution is (6, 4 )
I need help with the following question
Answer:
a. 2
b. x²+10x+26
c. x²+2x+2
Step-by-step explanation:
To find each value, you plug in the x value into the function and solve.
a. 2
f(2)=(2)²-2(2)+2 [combine like terms]
f(2)=4-4+2
f(2)=2
---------------------------------------------------------------------------------------------------------
b. x²+10x+26
f(x+6)=(x+6)²-2(x+6)+2 [use FOIL method and distributive property]
f(x+6)=x²+12x+36-2x-12+2 [combine like terms]
f(x+6)=x²+10x+26
---------------------------------------------------------------------------------------------------------
c. x²+2x+2
f(-x)=(-x)²-2(-x)+2 [combine like terms]
f(-x)=x²+2x+2
In terms of the trigonometric ratios for ΔABD, what is the length of line segment BD?
In terms of the trigonometric ratios for ΔABD, what is the length of line segment BD?
Answer:
[tex] BD = c*sin(A) [/tex]
[tex] BD = c*cos(B) [/tex]
[tex] BD = b*tan(A) [/tex]
Step-by-step explanation:
∆ABD is a right triangle.
Recall: trigonometric ratios of any right triangle can easily be understood or remembered with the acronym, SOHCAHTOA.
SOH => sin(θ) = opposite/hypotenuse
CAH => Cos(θ) = adjacent/hypotenuse
TOA = tan(θ) = opposite/adjacent
Thus, the length of segment BD, in terms of trigonometric ratios for ∆ABD can be done as follows:
Let BD = x
AB = c
AD = b
=>The sine ratio for the length of line segment BD = x, using SOH.
θ = A
Opposite = DB = x
hypotenuse = AB = c
[tex] sin(A) = \frac{x}{c} [/tex]
Make x the subject of formula.
[tex] c*sin(A) = x [/tex]
[tex] BD = x = c*sin(A) [/tex]
=>The Cosine ratio for the length of line segment BD = x, using CAH
θ = B
Adjacent = DB = x
hypotenuse = AB = c
[tex] cos(B) = \frac{x}{c} [/tex]
Make x the subject of formula.
[tex] c*cos(B) = x [/tex]
[tex] BD = x = c*cos(B) [/tex]
=>The Tangent ratio for the length of line segment BD = x, using TOA
θ = A
Adjacent = DB = x
hypotenuse = AD = b
[tex] tan(A) = \frac{x}{b} [/tex]
Make x the subject of formula.
[tex] b*tan(A) = x [/tex]
[tex] BD = x = b*tan(A) [/tex]
What is the midline equation of the function h(x) = -4 cos(5x - 9) - 7?
Answer: Midline equation: y = -7
Step-by-step explanation: This function is a sinusoidal function of the form:
y = a.cos(b(x+c))+d
Midline is a horizontal line where the function oscillates above and below.
In the sinusoidal function d represents its vertical shift. Midline is not influenced by any other value except vertical shift. For that reason,
Midline, for the function: [tex]h(x) = -4cos(5x-9) - 7[/tex] is y=d, i.e., [tex]y=-7[/tex]
Answer:
y=-7
Step-by-step explanation:
Scores on a University exam are normally distributed with a mean of 68 and a standard deviation of 9. Using the 68-95-99.7 rule, what percentage of students score above 77?
Answer:
0.1585, or 15.85%
Step-by-step explanation:
On a standard bell curve, the area from 77 to 100 falls within the 95.45 to 99.73 range.
99.73 - 68.27 = 31.46
31.46 / 2 =15.73
99.7 - 68 = 31.7
31.7 / 2 = 15.85
PLEASE HELP!!!!!! TIMED QUESTION!!!! FIRST CORRECT ANSWER WILL GET BRAINLIEST....PLEASE ANSWER NOW!!!!
The bar graph shows the number of students who earned each letter grade on an
exam, which statement about the graph is true?
1)
1/5 of the students earned a C
2)
3% more students earned an A then B
3)
20% of the students earned a D
4)
1/4 of the class earned a B
Answer:
Option (3)
Step-by-step explanation:
From the picture attached,
Bar graph sketched shows the grades earned by the students in an exam.
Number of students who achieved the grade A = 17
Number of students who achieved grade B = 14
Number of students with grade C = 5
Number of students with grade D = 9
Total students who took the exam = 17 + 14 + 5 + 9 = 45
Option (1)
"[tex]\frac{1}{5}[/tex] of the students earned a C"
Fraction of students who earned C = [tex]\frac{\text{Students who earned C}}{\text{Total students}}[/tex]
= [tex]\frac{5}{45}[/tex]
= [tex]\frac{1}{9}[/tex]
Therefore, this option is incorrect.
Option (2)
"3% more students earned an A then B"
Percentage of students who earned A = [tex]\frac{\text{Students got A}}{\text{Total students who took the exam}}\times 100[/tex]
= [tex]\frac{17}{45}\times 100[/tex]
= 37.78%
Percentage of students who earned B = [tex]\frac{\text{Students got B}}{\text{Total students who took the exam}}\times 100[/tex]
= [tex]\frac{14}{45}\times 100[/tex]
= 31.11%
Difference in percentage = 37.78 - 31.11
= 6.67%
Therefore, this option is not correct.
Option (3)
"20% of the students earned a D"
Percentage of students who earned D = [tex]\frac{\text{Students got D}}{\text{Total students who took the exam}}\times 100[/tex]
= [tex]\frac{9}{45}\times 100[/tex]
= 20%
Option (3) is the correct option.
Option (4)
" [tex]\frac{1}{4}[/tex] of the class earned a B"
Fraction of class who earned B = [tex]\frac{\text{Students got B}}{\text{Total students who took the exam}}[/tex]
= [tex]\frac{14}{45}[/tex]
Therefore, Option (4) is not correct.
The graph of g(x) = x – 8 is a transformation of the graph of f(x) = x. Which of
the following describes the transformation?
(A) translation 8 units down
(B) translation 8 units up
(C) translation 8 units right
(D) translation 8 units left
Determine the Perimeter of the shape #1.
Answer:
56.8
Step-by-step explanation:
7.1*8=56.8
Bette had 280 kilograms of bolts and put the same amount into each of 8 boxes. How
much will the bolts weigh in each box?
Answer:
35
Step-by-step explanation:
You have to divide 280 by 8 and that's how you get it.
] You are scheduled to receive $20,000 in two years. When you receive it, you will invest it for six more years at 8.4 percent per year. How much will you have in eight years?
Answer:
32449.3
Step-by-step explanation:
use the formula A = P(1+r / 100)^t
20000 × (1+ (8.4 / 100))^6
=32449.3
Max believes that the sales of coffee at his coffee shop depend upon the weather. He has taken a sample of 5 days. Below you are given the results of the sample.
Cups of Coffee Sold Temperature
350 50
200 60
210 70
100 80
60 90
40 100
A. Which variable is the dependent variable?
B. Compute the least squares estimated line.
C. Compute the correlation coefficient between temperature and the sales of coffee.
D. Predict sales of a 90 degree day.
Answer:
1. cups of coffee sold
2.Y = 605.7 - 5.943x
3. -0.952
4. 70.84
Step-by-step explanation:
1. the dependent variable in this question is the cups of coffee sold
2. least square estimation line
Y = a+bx
we have y as the cups of coffee sold
x as temperature.
first we will have to solve for a and then b
∑X = 450
∑Y = 960
∑XY = 61600
∑X² = 35500
∑Y² = 221800
a = ∑y∑x²-∑x∑xy/n∑x²-(∑x)²
a = 960 * 35500-450*61600/6*35500-450²
a = 6360000/10500
= 605.7
b = n∑xy - ∑x∑y/n∑x²-(∑x)²
= 6*61600 - 450*960/6*35500 - 450²
= -5.943
the regression line
Y = a + bx
Y = 605.7 - 5.943x
3. we are to find correlation coefficient
r = n∑xy - ∑x∑y multiplied by√(n∑x²-(∑x)² * (n∑y² - (∑y)²)
= 6*61600 -960*450/√(6*35500 - 450²)*(6*221800 - 960²)
=-62400/√4296600000
= -62400/65548.5
= -0.952
4. we have to predict sales of a 90 degree day fro the regression line
Y = 605.7 - 5.943x
y = 605.7 - 5.943(90)
y = 605.7 - 534.87
= 70.84
Draw the function
[tex]y = \tan(x) [/tex]
on the interval [-pi, pi]
Answer:
The answer is in the photo below. The interval is (-pi, pi) and the function is y = tanx.
10-
What is the equation of the line that is perpendicular to
the given line and passes through the point (2, 6)?
8-
(2,6)
-6
O x = 2
4
O x = 6
-2
-10 -3 -6 -22
2
4
B
8
10
X
O y = 2
O y = 6
(-34)
(814)
8
WO
Answer:
x = 2
Step-by-step explanation:
This blue line seems to be horizontal, and so a line perpendicular would have to be vertical. The only vertical line that passes through (2, 6) would be x = 2.
The equation of the line perpendicular to the given line and passes through the point (2, 6) is x = 2.
What is the Equation of line in Slope Intercept form?Equation of a line in slope intercept form is y = mx + b, where m is the slope of the line and b is the y intercept, which is the y coordinate of the point where it touches the Y axis.
Given is a line that passes through the points (-8, -4) and (8, -4).
This line is parallel to the X axis.
A line parallel to X axis has the equation y = b.
The y coordinate is -4 throughout the line.
So equation of the line is y = -4.
A line perpendicular to the given line will be parallel to Y axis.
Parallel lines to Y axis has the equation of the form x = a.
Line passes through the point (2, 6).
x coordinate will be 2 throughout.
So the equation of the perpendicular line is x = 2.
Hence the required equation is x = 2.
Learn more about Equations of Lines here :
https://brainly.com/question/21511618
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I am performing a before and after evaluation on 30 students who have taken a keyboarding class. I want to see if the course improved their words per minute keyed.
Required:
a. State the Null and Alternate Hypothesis.
b. The statistic that I would use is:_________
c. What would my t critical be for this calculation at a 0.10 level of significance?
d. If my t calculated = 1.62, would I reject or fail to reject the null hypothesis?
Answer:
a)
H₀ : µd = 0
H₁ : µd < 0
b)
The test statistic is
tₙ₋₁ = α / s√n
c)
at 0.10 level of significance,
tₙ₋₁ , ₐ
t₃₀₋₁ , ₀.₁₀ = t₂₉, ₀.₁₀ = 1.311
d)
given that T(critical) = 1.62
∴ T(critical) = 1.62 > t₂₉, ₀.₁₀ = 1.311
at 10% level of significance,
REJECT H₀
Since 1.62 > 1.311, we can reject the null hypothesis.
Noel pays $1.54 in sales tax.The sales tax rate is 5.5%,what the original price
Step-by-step explanation:
Hi, there!!!
Let's simply work with it,
Here,
tax=$1.54
rate of tax= 5.5%
now, let the original price be x.
so, 5.5% of x= $1.54 { tax amount = tax% of original price}.
or, 5.5/100 × x= $1.54
or, 5.5x = $1.54×100
or, x= $28.
Therefore, the original price was $28.
Hope it helps...
Mr. Vazquez determines that the area of a bathroom in his house is 25 square feet less than 1/5 of the area of the living room. If the bathroom measures 35 square feet, what is the area of the living room?\
Answer:
300 SF
Step-by-step explanation:
just took the test
Another trader would like to carry out a hypothesis test about stocks that offer dividends. Why is this hypothesis test right-tailed? Select the correct answer below: This is a right-tailed test because a direction is not specified. This is a right-tailed test because a direction is specified. The population parameter is greater than the specified value. This is a right-tailed test because a direction is specified. The population parameter is less than the specified value. More information is needed.
Answer:
This is a right-tailed test because a direction is specified. The population parameter is greater than the specified value.
Step-by-step explanation:
The hypothesis testing technique is used to test an assumption regarding population parameter. Null hypothesis is a statement that is to be tested against the alternative hypothesis and then decision is taken whether to accept or reject the null hypothesis. A right tailed test is where the most of data is in the right side. This is one tailed test where the direction is specified.
I need help please help me!
Answer:
36ft³
Step-by-step explanation:
Bottom rectangular prism: 2x2x6=24
Top rectangular prism: 2x2x3=12
24+12=36ft³
Answer:
[tex]\boxed{36ft^3}[/tex]
Step-by-step explanation:
Hey there!
Well to solve for V we need to find the volume of the 2 rectangular prism's given.
Rec#1: 2•3•2 = 12
Rec#2: 6•2•2 = 24
Rec#1 + Rec#2 = V
12 + 24 = 36ft³
Hope this helps :)
The average of 4 numbers is 15 , the sum of 3 numbers is 14 what is the fourth number
Answer:
46
Step-by-step explanation:
(14+x)/4 = 15
14 + x = 60
x = 46
Answer:
46
Step-by-step explanation:
Let a to d be number 1 to 4 respectively.
15 = (a + b + c + d) / 4
(a + b + c + d) = 60 ------> total sum of the 4 numbers
Since the sum of 3 numbers (assuming a to c) is 14,
Fourth number (d) = 60 - 14
= 46
That's how I would do it, hope this helps :)
Solve Logarithm 5(2^x+4)=15. Round to the nearest thousandth. A.1.089 B.2.415 C.0.657 D.3.982
[tex]5(2^x+4)=15\\2^x+4=3\\2^x=-1\\x\in\emptyset[/tex]
Answer:
no solutions
Step-by-step explanation:
5(2^x+4)=15
Divide each side by 5
5/5(2^x+4)=15/5
(2^x+4)=3
Subtract 4 from each side
2^x = 3-4
2^x = -1
This cannot happen so there are no solutions
I really need help here I am super confused
Which of the following steps can be performed so that the square root property may easily be applied to 2x^2=16?(1 point)
The square root property requires a quantity squared by itself on one side of the equation. The only quantity squared is 16, so divide both sides by 2 before applying the square root property.
The square root property requires a quantity squared by itself on one side of the equation. The only quantity squared is x, so divide both sides by 2 before applying the square root property.
The square root property requires a quantity squared by itself on one side of the equation. The only quantity squared is 16, so divide both sides by 16 before applying the square root property.
The square root property requires a quantity squared by itself on one side of the equation. The only quantity squared is x, so divide both sides by 16 before applying the square root property.
Which of the following steps would not be necessary when using the square root property to solve a quadratic equation?(1 point)
The square root property may be applied only if the constant is positive.
Isolate the quantity being squared.
After applying the square root property, solve the resulting equations. When taking the square root of both sides, use ± on the square root of the constant.
Answer:
The square root property requires a quantity squared by itself on one side of the equation. The only quantity squared is x, so divide both sides by 2 before applying the square root property.
Step-by-step explanation:
In the above question, we are given the expression: 2x^2=16 and we are asked the proper way to apply the square root property.
2x² = 16 is an algebraic equation
To apply square root property to an expression, there must be only one quantity that is squared.
Step 1
We divide both sides by 2
This is because we have to first eliminate the coefficient of x
2x²/2 = 16/2
x² = 8
Step 2
Now that we have eliminated the coefficient of x², we can apply the square root property now because x is the only quantity that is squared.
√x² = √8
x = √8
Therefore, Option 2 which says: "The square root property requires a quantity squared by itself on one side of the equation. The only quantity squared is x, so divide both sides by 2 before applying the square root property." is the correct option
10 - 2x, when x = 3
Answer:
4
Step-by-step explanation:
Plug in 3 as x in the expression:
10 - 2x
10 - 2(3)
10 - 6
= 4
Answer:
4
Step-by-step explanation:
10 - 2x
Let x =3
10 -2(3)
10 -6
4
1. Why is money better than a bartering system?
A People might not have items to trade.
B It helps people to agree on the value of something.
C People might lose track of their money.
D Both A and B
E Both B and C
The correct answer is D. Both A and B
Explanation:
Bartering is an economic system in which products are directly exchanged for other products. For example, a pound of oranges is exchanged for a pound of rice. Due to this, in bartering, there is no money or elements such as coins or bills that represent the value of products or services. This system has both advantages and disadvantages in comparison to the use of money.
In terms of disadvantages, bartering implies individuals need products or services they can use to exchange, which might not be possible for all individuals as not all individuals might produce a product or have a product other are interested in. Also, in bartering the value of products varies, for example, a pound of blueberries can be equal to a pound of rice, three pounds of rice, or even half pound of rice, as values change according to the situation of those participating in the exchange. This means, in bartering the value fluctuates and it is more difficult to agree on the value of something, which does not occur if money is used as each product has a defined price which might just vary slightly. According to this, options A and B are advantages of money over bartering.
Someone please help me ASAP
Answer:
x > -7/3
Step-by-step explanation:
-3x+8 < 15
Subtract 8 from each side
-3x+8-8 < 15-8
-3x < 7
Divide by 3 remembering to flip the inequality
-3x/-3 > 7/-3
x > -7/3
Answer:
[tex]x <-\frac{7}{3}[/tex]
A TV studio has brought in 8 boy kittens and 9 girl kittens for a cat food commercial. The director is going to choose 11 of these kittens at random to be in the commercial. What is the probability that the director chooses 4 boy kittens and 7 girl kittens? Round your answer to three decimal places.
Answer:
0.204
Step-by-step explanation:
The formula to use to solve this is the combination formula.
Combination formula =
C(n, r) = nCr = n!/r! (n - r)!
Total number of kittens = 8 boy kittens + 9 girl kittens
= 17 kittens
Step 1
We find the probability of choosing 4 boy kittens out of 8 boy kittens
= 8C4 = 8!/4! × (8 - 4)!
= 8C4 = 8! / 4! × 4!
= 8C4 = 8 × 7 × 6 × 5 × 4 × 3 × 2 × 1/ (4 × 3 × 2 × 1) × (4 × 3 × 2 × 1)
8C4 = 70
Step 2
We find the probability of choosing 7 girl kittens out of 9 girl kittens
9C7 = 9!/7! × (9 - 7)!
= 9C7 = 9! / 7! × 2!
= 9C7 = 9 × 8 × 7 × 6 × 5 × 4 × 3 × 2 × 1/ (7 × 6 × 5 × 4 × 3 × 2 × 1) × (2 × 1)
9C7 = 36
Step 3
Find the probability of Picking 11 kittens out of 17 kittens
17C11 = 17!/11! × (17 - 11)!
= 17C11 = 17! / 11! × 6!
= 17C11 = 17 × 16 × 15 × 14 × 13 × 12 × 11 × 10 × 9 × 8 × 7 × 6 × 5 × 4 × 3 × 2 × 1/ (11 × 10 × 9 × 8 × 7 × 6 × 5 × 4 × 3 × 2 × 1) × (6 × 5 × 4 × 3 × 2 × 1)
17C11 = 12,376
Step 4
The final step
The probability that the director chooses 4 boy kittens and 7 girl kittens
= 8C4 × 9C7/ 17C11
= 70 × 36/12376
= 2520/12376
= 0.2036199095
Approximately to 3 decimal places = 0.204
Therefore, the probability that the director chooses 4 boy kittens and 7 girl kittens is 0.204
An article contained the following observations on degree of polymerization for paper specimens for which viscosity times concentration fell in a certain middle range:
418 421 421 422 425 428 431 435 437
438 445 447 448 453 458 462 465
(c) Calculate a two-sided 95% confidence interval for true average degree of polymerization. (Round your answers to two decimal places.) Note that it is plausible that the given sample observations were selected from a normal distribution and there are no outliers.
(___ , ___)
Does the interval suggest that 441 is a plausible value for true average degree of polymerization?
Yes or No
Does the interval suggest that 451 is a plausible value?
Yes or No
Answer:
Step-by-step explanation:
Form a set of values we get
n = 17
And with the help of a calculator
μ₀ = 438,47
σ = 14,79
Normal Distribution is : N ( 438,47 ; 14,79 )
c)
CI = 95 % means α = 5 % α/2 = 2,5 % α/2 = 0,025
and as n < 30 we should use t-student distribution with n -1 degree of freedom df = 16. t score for 0,025 and 16 s from t-table 2,120
By definition:
CI = [ μ₀ ± t α/2 ; n-1 * σ/√n ]
CI = [ μ₀ ± 2,120* 14,79/√17 ]
CI = [ μ₀ ± 7,60 ]
CI = [ 438,47 ± 7,60 ]
CI = [ 430,87 ; 446,07 ]
95% confidence interval for true average degree of polymerization is [430.87 ; 446.07] and this interval suggest that 441 is a plausible value for true average degree of polymerization and also this interval does not suggest that 451 is a plausible value.
Given :
Sample = [ 418, 421, 421, 422, 425, 428, 431, 435, 437, 438, 445, 447, 448, 453, 458, 462, 465 ]95% confidence interval.The total number of values given is, n = 17
Mean, [tex]\mu_0=438.47[/tex]
Standard Deviation, [tex]\sigma = 14.79[/tex]
The normal distribution is given by: N (438.47 ; 14.79)
If Cl is 95% then [tex]\alpha[/tex] is 5% and [tex]\alpha /2[/tex] is 2.5%
[tex]\alpha /2 = 0.025[/tex]
Now, use t-statistics distribution with (n-1) degree of freedom df = 16
So, the t score for 0.025 and 16 s from t-table 2.120.
[tex]\rm Cl = [\mu_0 \pm t_{\alpha /2};(n-1)\times \dfrac{\sigma}{\sqrt{n} }][/tex]
[tex]\rm Cl = [\mu_0 \pm 2.120\times \dfrac{14.79}{\sqrt{17} }][/tex]
[tex]\rm Cl = [\mu_0 \pm 7.60][/tex]
Cl = [430.87 ; 446.07]
Yes, the interval suggests that 441 is a plausible value for true average degree of polymerization.
No, the interval does not suggest that 451 is a plausible value.
For more information, refer to the link given below;
https://brainly.com/question/2561151
Determine the area of the shape above. The formula for the area of a polygon is: Area = 1/2 (a n s) *
Step-by-step explanation:
Area of a regular polygon is half the apothem times the perimeter, or A = ½ a n s, where a is the apothem, n is the number of sides, and s is the side length.
A = ½ (8.5705 in) (8) (7.1 in)
A = 243.4022 in²
Translate and solve: 82 less than a is at least -82
Answer:
a≥0
Step-by-step explanation:
a-82≥-82
a≥-82+82
a≥0
Find a • b. a = 5i + 7j, b = -4i + 3j 1 41
Answer:
[tex]\boxed{-20i^2 -13ij+21j^2}[/tex]
Step-by-step explanation:
[tex]\sf Plug \ in \ the \ values.[/tex]
[tex](5i+7j) \cdot (-4i+3j)[/tex]
[tex]\sf Expand \ brackets.[/tex]
[tex]5i(-4i+3j)+7j(-4i+3j)[/tex]
[tex]-20i^2 +15ij+-28ij +21j^2[/tex]
[tex]\sf Combine \ like \ terms.[/tex]
[tex]-20i^2 -13ij+21j^2[/tex]
A plane took off at a point that is 42 meters from the control tower. The flight path takes the plane over the control tower that is 98 meters high. After traveling 83 meters, which statement is most accurate?
A. The plane needs to be about 15 meters higher to clear the tower.
B. The plane clears the tower with about 27 meters to spare.
C. The plane clears the tower with about 15 meters to spare.
D. The plane needs to be about 27 meters higher to clear the tower.
Answer:
D. The plane needs to be about 27 meters higher to clear the tower.
Step-by-step explanation:
In this scenario a triangle is being formed. The base the plane's takeoff point to the tower base which is 42 meters (x).
The hypothenus is the distance travelled by the plane which is 83 meters (h)
The height of the tower is 98 Meters
We want to calculate the height of our triangle (y) so we can guage if the plane scaled the tower.
According to Pythagorean theorem
(x^2) + (y^2) = h^2
y = √ (h^2) - (x^2)
y = √ (83^2) - (42^2)
y= √(6889 - 1764)
y= 71.59 Meters
The height from the plane's position to the top of the tower will be
Height difference = 98 - 71.59 = 26.41 Meters
So the plane should go about 27 Meters higher to clear the tower
What is the mulitplicative rate of change for the exponential function f(x) = 2 (5over2) to the negative x power ?
Answer:
2/5
Step-by-step explanation:
f(x) = 2(5/2)^-x = 2(2/5)^x
The multiplicative rate of change is the base of the positive exponent, 2/5.
