Answer:
14 + 25l + 6l^2
Step-by-step explanation:
(7 + 2i) (2 + 3i)
=> 14 + 4l + 21l + 6l^2
=> 14 + 25l + 6l^2
This is the correct answer
Two samples from the same population both have M = 84 and s2 = 20, but one sample has n = 10 and the other has n = 20 scores. Both samples are used to evaluate a hypothesis stating that μ = 80 and to compute Cohen’s d. How will the outcomes for the two samples compare?
Complete Question
Two samples from the same population both have M = 84 and s2 = 20, but one sample has n = 10 and the other has n = 20 scores. Both samples are used to evaluate a hypothesis stating that μ = 80 and to compute Cohen’s d. How will the outcomes for the two samples compare?
a.
The larger sample is more likely to reject the hypothesis and will produce a larger value for Cohen’s d.
b.
The larger sample is more likely to reject the hypothesis, but the two samples will have the same value for Cohen’s d.
c.
The larger sample is less likely to reject the hypothesis and will produce a larger value for Cohen’s d.
d.
The larger sample is less likely to reject the hypothesis, but the two samples will have the same value for Cohen’s d.
Answer:
The Cohen's d value is [tex]d = 0.895[/tex]
The correct option is b
Step-by-step explanation:
From the question we are told that
The sample mean of each population is [tex]M = 84[/tex]
The variance of each population is [tex]s^2 = 20[/tex]
The first sample size is [tex]n_1 = 10[/tex]
The second sample size is [tex]n_2 = 20[/tex]
The null hypothesis is [tex]H_o : \mu = 80[/tex]
Generally the standard deviation is mathematically evaluated as
[tex]s = \sqrt{20 }[/tex]
=> [tex]s = 4.47[/tex]
The first test statistics is evaluated as
[tex]t_1 = \frac{M - \mu }{ \frac{\sigma }{ \sqrt{n_1} } }[/tex]
=> [tex]t_1 = \frac{84 - 80 }{ \frac{4.47 }{ \sqrt{10} } }[/tex]
=> [tex]t_1 = 2.8298[/tex]
The second test statistics is evaluated as
[tex]t_2 = \frac{M - \mu }{ \frac{\sigma }{ \sqrt{n_2} } }[/tex]
=> [tex]t_2 = \frac{84 - 80 }{ \frac{4.47 }{ \sqrt{20} } }[/tex]
=> [tex]t_2 = 4.0[/tex]
The sample with the larger test statistics (sample size) will more likely reject the null hypothesis
Generally the Cohen's d value is mathematically evaluated as
[tex]d = \frac{M - \mu }{s }[/tex]
=> [tex]d = \frac{ 84 - 80 }{4.47 }[/tex]
=> [tex]d = 0.895[/tex]
Given that the the sample mean and sample size are the same for both sample the Cohen's d value will be the same
Convert 6 feet to miles ( round five decimal places
Answer:
0.00114
Step-by-step explanation:
Divide length value by 5280
An opinion poll asked a random sample of adults whether they believe flu shots are ineffective in the United States. A commentator believes less than 35% of all adults believe they are ineffective. Which null and alternative hypotheses should be used to test this claim? H0: p ≠ 0.35, Ha: p 0.35
Complete Question
The complete question is shown on the first uploaded image
Answer:
The second option is the correct option
Step-by-step explanation:
From the question we are told that
The sample proportion is [tex]\r p = 0.35[/tex]
The Null Hypothesis is [tex]H_o : \r p = 0.35[/tex]
The reason for this is that the this original claim when represented mathematically does not contain an equality sign ([tex]i.e \ it \ is \ mathematically \ represented \ as \ \r p < 0.35[/tex]) so the null hypothesis is the compliment of it ( i.e [tex]\r p = 0.35[/tex])
The Alternative hypothesis is [tex]H_a : \r p < 0.35[/tex]
PLEASE ANSWER! Which expression is equal to the length of the hypotenuse of a right triangle, formed inside the unit circle, with a radius of 1?
A: sin 0/ cos 0
B: sin^2 0 + tan^2 0
C: sin 0 + cos 0
D: sin^2 0 + cos^2 0
Answer:
b
Step-by-step explanation:
b: sin^2 0 + tan^2 0 this is just a gut feelings its been awhile since i done this kind of think i hope i could help
The expression equal to the length of the hypotenuse of a right triangle formed inside the unit circle with a radius of 1 is Option (D) [tex]sin^{2}[/tex]θ+[tex]cos^{2}[/tex]θ
What is Right triangle?A right-angled triangle is a type of triangle that has one of its angles equal to 90 degrees.
What is Hypotenuse?A hypotenuse is the longest side of a right-angled triangle, the side opposite the right angle.
Here,
The length of the hypotenuse of a right triangle, formed inside the unit circle, with a radius of 1 is 1 unit.
We know that,
[tex]sin^{2}[/tex]θ+[tex]cos^{2}[/tex]θ=1
Hence, The expression equal to the length of the hypotenuse of a right triangle formed inside the unit circle with a radius of 1 is Option (D) [tex]sin^{2}[/tex]θ+[tex]cos^{2}[/tex]θ
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7 students in a class,3/4 th pound of a cake .divide cake each student?
Answer:
9 1/3
Step-by-step explanation:
1. Set up the equation and solve
7 ÷ 3/4 = 9 1/3
Answer:
3/28 pounds or approximately 0.107 pounds
Step-by-step explanation:
To find out the amount of cake that each of the 7 students would get, we simply need to split the 3/4th pounds of cake amongst the 7 students.
Simply write the equation as follows:
(3/4)/7 = 3/28
So each student would get 3/28 of a pound of cake which is approximately 0.107 pounds of cake.
Cheers.
A market survey shows that 50% of the population used Brand Z computers last year, 4% of the population quit their jobs last year, and 2% of the population used Brand Z computers and then quit their jobs. Are the events of using Brand Z computers and quitting your job independent
Answer:
the events of using Brand Z computers and quitting your job are independent.
Step-by-step explanation:
Let A be the event that the population used Brand Z computers and let B be the event that the population quit their jobs.
We are told that 50% of the population used Brand Z computers last year. Thus, the probability of event A is;
P(A) = 50% = 0.5
Also, we are told that 4% of the population quit their jobs last year. Thus the probability of event B is;
P(B) = 4% = 0.04
Since 2% of the population used Brand Z computers and then quit their jobs. Then the probability of the population used Brand Z computers and then quit their jobs is;
P(A ∩ B) = 2% = 0.02
From the law of independent events, if A and B are to be independent events, then;
P(A ∩ B) = P(A) × P(B)
Thus;
P(A ∩ B) = 0.5 × 0.04 = 0.02
This is same value as what was given in the question, thus the events of using Brand Z computers and quitting your job are independent.
Which point lies on the line with point-slope equation y - 3 = 4(x + 7)?
A.
(7, 3)
B.
(7, -3)
C.
(-7, -3)
D.
(-7, 3)
Answer:
D. (-7, 3)
Step-by-step explanation:
The equation given is in point-slope form.
Point-slope form is:
y-y1=m(x-x1)
This is where:
y1 is the y-coordinate of a point it goes through
m is the slope of the line
x1 is the x-coordinate of a point that it goes through
That said, in the given equation:
y1=3
m=4
x1=-7
Note that a point is (x-coordinate, y-coordinate)
Therefore, (-7, 3) is the point that lies on the line.
Ted has to gift wrap a box of chocolates that is shaped like a triangular prism. What is the minimum amount of wrapping paper he needs?
Answer:
69.48 square inches
Step-by-step explanation:
The amount of wrapping paper needed = surface area of the triangular prism
Surface area of triangular prism is given as, area = Perimeter of triangular base*height of prism + 2(base area)
Perimeter of triangular base = sum of the 3 sides of the prism
Perimeter of base = 3.5 + 3.5 + 3 = 10 inches
Height of prism = 6 inches
Base area = ½*base of triangle * height of triangle = ½*3*3.16 = 4.74 in²
Surface area of triangular prism = [tex] 10*6 + 2(4.74) [/tex]
[tex] S.A = 60 + 9.48 = 69.48 in^2[/tex]
Amount of wrapping paper needed is 69.48 square inches .
coefficient of 8x+7y
Answer:
8
Step-by-step explanation:
Identify the exponents on the variables in each term, and add them together to find the degree of each term.
8x→1
7y→1
The largest exponent is the degree of the polynomial.
1
The leading term in a polynomial is the term with the highest degree.
8x
The leading coefficient of a polynomial is the coefficient of the leading term.
____________________________________________________________
The leading term in a polynomial is the term with the highest degree.
8x
The leading coefficient in a polynomial is the coefficient of the leading term.
8
List the results.
Polynomial Degree: 1
Leading Term: 8x
Leading Coefficient: 8
Hope This Helps!!!
Suppose your weekly local lottery has a winning chance of 1/106. You buy lottery from them for x weeks in a row. What is the probability that you never win?
Answer:
The probability mass function that you never win [tex]^xC_o[/tex] = [tex](\dfrac{999999}{1000000})^x[/tex]
Step-by-step explanation:
Given that;
the winning chance of a weekly local lottery = [tex]\dfrac{1}{10^6}[/tex]
= [tex]\dfrac{1}{1000000}[/tex]
The probability of losing = 1 - probability of winning (winning chance)
The probability of losing = [tex]1- \dfrac{1}{1000000}[/tex]
The probability of losing =[tex]\dfrac{999999}{1000000}[/tex]
The probability mass function that you never win [tex]^xC_o[/tex] = [tex](\dfrac{1}{10^6} )^0 ( \dfrac{999999}{1000000})^x[/tex]
The probability mass function that you never win [tex]^xC_o[/tex] = [tex](\dfrac{999999}{1000000})^x[/tex]
A random sample of 12 supermarkets from Region 1 had mean sales of 84 with a standard deviation of 6.6. A random sample of 17 supermarkets from Region 2 had a mean sales of 78.3 with a standard deviation of 8.5. Does the test marketing reveal a difference in potential mean sales per market in Region 2? Let μ1 be the mean sales per market in Region 1 and μ2 be the mean sales per market in Region 2. Use a significance level of α=0.02 for the test. Assume that the population variances are not equal and that the two populations are norm
Answer:
We conclude that there is no difference in potential mean sales per market in Region 1 and 2.
Step-by-step explanation:
We are given that a random sample of 12 supermarkets from Region 1 had mean sales of 84 with a standard deviation of 6.6.
A random sample of 17 supermarkets from Region 2 had a mean sales of 78.3 with a standard deviation of 8.5.
Let [tex]\mu_1[/tex] = mean sales per market in Region 1.
[tex]\mu_2[/tex] = mean sales per market in Region 2.
So, Null Hypothesis, [tex]H_0[/tex] : [tex]\mu_1-\mu_2[/tex] = 0 {means that there is no difference in potential mean sales per market in Region 1 and 2}
Alternate Hypothesis, [tex]H_A[/tex] : > [tex]\mu_1-\mu_2\neq[/tex] 0 {means that there is a difference in potential mean sales per market in Region 1 and 2}
The test statistics that will be used here is Two-sample t-test statistics because we don't know about population standard deviations;
T.S. = [tex]\frac{(\bar X_1 -\bar X_2)-(\mu_1-\mu_2)}{s_p \times \sqrt{\frac{1}{n_1}+ {\frac{1}{n_2}}} }[/tex] ~ [tex]t__n_1_+_n_2_-_2[/tex]
where, [tex]\bar X_1[/tex] = sample mean sales in Region 1 = 84
[tex]\bar X_2[/tex] = sample mean sales in Region 2 = 78.3
[tex]s_1[/tex] = sample standard deviation of sales in Region 1 = 6.6
[tex]s_2[/tex] = sample standard deviation of sales in Region 2 = 8.5
[tex]n_1[/tex] = sample of supermarkets from Region 1 = 12
[tex]n_2[/tex] = sample of supermarkets from Region 2 = 17
Also, [tex]s_p=\sqrt{\frac{(n_1-1)\times s_1^{2}+(n_2-1)\times s_2^{2} }{n_1+n_2-2} }[/tex] = [tex]s_p=\sqrt{\frac{(12-1)\times 6.6^{2}+(17-1)\times 8.5^{2} }{12+17-2} }[/tex] = 7.782
So, the test statistics = [tex]\frac{(84-78.3)-(0)}{7.782 \times \sqrt{\frac{1}{12}+ {\frac{1}{17}}} }[/tex] ~ [tex]t_2_7[/tex]
= 1.943
The value of t-test statistics is 1.943.
Now, at a 0.02 level of significance, the t table gives a critical value of -2.472 and 2.473 at 27 degrees of freedom for the two-tailed test.
Since the value of our test statistics lies within the range of critical values of t, so we have insufficient evidence to reject our null hypothesis as it will not fall in the rejection region.
Therefore, we conclude that there is no difference in potential mean sales per market in Region 1 and 2.
Given the function f ( x ) = 2 x + 8 , evaluate and simplify the expressions below. See special instructions on how to enter your answers.
Answer:
[tex]f(a) = 2a + 8[/tex]
[tex]f(x + h) = 2x + 2h + 8[/tex]
[tex]\frac{f(x + h) - f(x)}{h} = 2[/tex]
Step-by-step explanation:
Given
[tex]f(x) = 2x + 8[/tex]
Required
[tex]f(a)[/tex]
[tex]f(x + h)[/tex]
[tex]\frac{f(x + h) - f(x)}{h}[/tex]
Solving for f(a)
Substitute a for x in the given parameter
[tex]f(x) = 2x + 8[/tex] becomes
[tex]f(a) = 2a + 8[/tex]
Solving for f(x+h)
Substitute x + h for x in the given parameter
[tex]f(x + h) = 2(x + h) + 8[/tex]
Open Bracket
[tex]f(x + h) = 2x + 2h + 8[/tex]
Solving for [tex]\frac{f(x + h) - f(x)}{h}[/tex]
Substitute 2x + 2h + 8 for f(x + h), 2x + 8 fof f(x)
[tex]\frac{f(x + h) - f(x)}{h}[/tex] becomes
[tex]\frac{2x + 2h + 8 - (2x + 8)}{h}[/tex]
Open Bracket
[tex]\frac{2x + 2h + 8 - 2x - 8}{h}[/tex]
Collect Like Terms
[tex]\frac{2x - 2x+ 2h + 8 - 8}{h}[/tex]
Evaluate the numerator
[tex]\frac{2h}{h}[/tex]
[tex]2[/tex]
Hence;
[tex]\frac{f(x + h) - f(x)}{h} = 2[/tex]
If x represents the rate that Joy traveled at for the first half of the trip, write an
expression that represents the amount of time it takes Joy to complete the second half of the
trip at the slower rate.
Answer:
time taken for trip 2nd half > time taken for trip 1st half
Step-by-step explanation:
Let the total distance of Joy's trip be = D
Then, the first half distance travelled = D/2
The rate (speed) at which Joy travels during first half = x
So, time taken to travel first half = Distance / Speed
= (D/2) / x = D / 2x
Second half of trip distance travelled = remaining D/2Let the rate (speed) at which Joy travels during second half = x'
As given, x' (second half speed) < x (first half speed)
So, time taken to travel first half = Distance / Speed
(D/2) / x' = D / 2x'
As x' < x : D / 2x' > D / 2x .
Trip 1st half Time taken trip < 2nd half ; or trip 2nd half time taken > 1st half
[tex]( \frac{3}{4} - \frac{2}{3} ) \times 1 \frac{1}{5} [/tex]
Answer: 0.1 or 1/10
Step-by-step explanation:
[tex]\left(\frac{3}{4}-\frac{2}{3}\right)\cdot \:1\frac{1}{5}[/tex]
[tex]1\frac{1}{5}=\frac{6}{5}[/tex]
[tex]\left(\frac{3}{4}-\frac{2}{3}\right)\cdot \frac{6}{5}[/tex]
[tex]\frac{3}{4}-\frac{2}{3}[/tex] [tex]=\frac{9}{12}-\frac{8}{12}[/tex]
[tex]=\frac{1}{12}[/tex]
[tex]\frac{6}{5}\cdot \frac{1}{12}[/tex]
Cross, cancel common factor
[tex]\frac{1}{2}\cdot \frac{1}{5}[/tex]
[tex]=\frac{1}{10}[/tex]
Quadrilateral ABCD is similiar to quadrilateral EFGH. The lengths of the three longest sides in quadrilateral ABCD are 60 feet, 40 feet, and 30 feet long. If the two shortest sides of quadrilateral EFGH are 6 feet long and 12 feet long, how long is the 2nd longest side on quadrilateral EFGH?
Answer:
24
Step-by-step explanation:
For ABCD the three longest are:
60,40,30
60 to 40 is 20
40 to 30 is 10
so each time it's decreasing by 1/2
For EFGH the two shortest are:
6 and 12
12 to 6 is 1/2
Assuming there is a pattern
it logically would be 24
as 12(2)=24
The Masim family’s monthly budget is shown in the circle graph provided in the image. The family has a current monthly income of $5,000. How much money do they spend on food each month? A. $250 B. $500 C. $750 D. 1,100 Please show ALL work! <3
Answer:
C. $750
Step-by-step explanation:
The amount of money to be spent monthly on food = percentage covered by food in the circle ÷ 100% × total monthly income
= [tex] \frac{15}{100}*5000 [/tex]
[tex] = \frac{15}{1}*50 [/tex]
[tex] 15*50 = 750 [/tex]
Amount of money spent each month by the Masims is $750.
Find the indicated complement. A certain group of women has a 0.12% rate of red/green color blindness. If a woman is randomly selected, what is the probability that she does not have red/green color blindness?
Answer:
the probability will be 0.
Step-by-step explanation:
0.12%= 0.0012= 3/2500.
Gavin goes to the market and buys one rectangle shaped board. The length of the board is 16 cm and width of board is 10 cm. If he wants to add a 2 cm wooden border around the board, what will be the area of the rectangle board?
Answer:
The answer is 216
Step-by-step explanation:
if there is a 2 cm border, that means that the sides will both become 2 centimeters longer. so (16+2)*(10*2) = 18*12 = 216.
i will give brainliest and 5 stars if you help ASAP
Use the probability distribution table to answer the question.
What is P(1 < X < 5)?
Enter your answer, as a decimal, in the box.
Add up the P(x) values that correspond to x = 2 through x = 4
0.07+0.22+0.22
So we have a 51% chance of getting an x value such that 1 < x < 5
By using the probability distribution table, the value of P(1<x<5) is 0.51
What is Probability?Probability is the branch of mathematics concerning numerical descriptions of how likely an event is to occur, or how likely it is that a proposition is true
What is Probability distribution?A probability distribution is the mathematical function that gives the probabilities of occurrence of different possible outcomes for an experiment. It is a mathematical description of a random phenomenon in terms of its sample space and the probabilities of events
Given,
We have to find the value of P(1<x<5)
P(1<x<5) = P(2)+P(3)+P(4)
P(2)=0.07
P(3)=0.22
P(4)=0.22
P(1<x<5) = 0.07+0.22+0.22 =0.51
Hence, the value of P(1<x<4)= 0.51
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Given the equation 3x+7 which order of operations completely solves for x
Answer-7/3
Step-by-step explanation:
Which represents a measure of volume?
O 5 cm
O 5 square cm
05 cm
05 cm
Answer:
5 cm³
Step-by-step explanation:
The correct options to the given question will be:
5 cm³ 5 square cm 5 cm 5 cm²The volume of a solid is referred to as the space that the figure occupies. The three dimensions are covered and recorded to measure the volume. It is measured by multiplying the length, breadth, and the height of the solid. Since three units are multiplies, therefore the unit of the volume becomes a cubic unit. Usually, the volume is measured in cubic meter or cubic centimetre.
Which equation demonstrates the additive identity property?
Answer:
See Explanation
Step-by-step explanation:
The options are not given; however, you can take a clue from my explanation to answer your question
Let x be a real number;
Additive identity property implies that; adding x to 0 or 0 to x gives x;
In other words;
[tex]x + 0 = x[/tex]
[tex]0 + x = x[/tex]
Note that x can be replaced with any real number; Take for instance
[tex]1 + 0 = 1[/tex]
[tex]0 + 2.5 = 2.5[/tex]
[tex]3 + 0 = 3[/tex]
There are uncountable number of examples;
However, take note that adding 0 to a given digit results in the exact digit and that's the implication of addition identity property
Answer:
(7+4i)+0=7+4i
Step-by-step explanation:
Determine which of the four levels of measurement (nominal, ordinal, interval, ratio) is most appropriate. Years in which U.S. presidents were inaugurated
Answer:
Interval Level of Measurement
Step-by-step explanation:
The Interval level of measurement highlights the distances between two measurements. These distances are meaningful and could be rated as low intervals or high intervals. Intervals also indicate class and order between measurements. The inauguration of the United States President is an event that occurs 72 to 78 days after the presidential election. It is usually done as a private and public oath-taking ceremony on January 20, four years after the last presidential election. So, even if the president is on a second term, this event must be held.
The last U.S presidential election occurred on January 20, 2017, and the next one will be held on January 21, 2021. So there is an interval of four years between the last and next U.S presidential inauguration ceremony.
In determining your group’s estimate, what mathematical model of a tennis ball did you use? What model of the classroom did you use? Did you make other simplification or assumptions?
Answer:
bro ur question is not understandable
Find the value of the variable(s) in each figure. Explain your reasoning. Thank you in advance
Answer:
1. x 55
2. y 117
x 51
3.x39
y116
4.x 18
5.x 48
y 14
for the last one I'm not sure. please give 5 start
9x - 3 -8x = 7 - x what is x Please answer ASAP, is urgent!!
Solve
Let's solve your equation step-by-step.
9x−3−8x=7−x
Step 1: Simplify both sides of the equation.
9x−3−8x=7−x
9x+−3+−8x=7+−x
(9x+−8x)+(−3)=−x+7(Combine Like Terms)
x+−3=−x+7
x−3=−x+7
Step 2: Add x to both sides.
x−3+x=−x+7+x
2x−3=7
Step 3: Add 3 to both sides.
2x−3+3=7+3
2x=10
Step 4: Divide both sides by 2.
2x
2
=
10
2
x=5
Answer:
x=5
Answer:
Hope this is easier, good luck.
Which polynomial function has zeros when ? A: B: C: D:
Suppose 50 percent of the customers at Pizza Palooza order a square pizza, 70 percent order a soft drink, and 35 percent order both a square pizza and a soft drink.
Required:
Is ordering a soft drink independent of ordering a square pizza? Explain
Answer:
Ordering a soft drink is independent of ordering a square pizza.
Step-by-step explanation:
20% more customers order a soft drink than pizza, therefore they cannot be intertwined.
Given: P(A)=0.5 & P(B)=.7
P(A∩B) = P(A) × P(B)
= 0.5 × .7
= 0.35
P(A∪B) = P(A) + P(B) - P(A∩B)
= 0.5 + .7 - 0.35
= 0.85
P(AΔB) = P(A) + P(B) - 2P(A∩B)
= 0.5 + .7 - 2×0.35
= 0.5
P(A') = 1 - P(A)
= 1 - 0.5
= 0.5
P(B') = 1 - P(B)
= 1 - .7
= 0.3
P((A∪B)') = 1 - P(A∪B)
= 1 - 0.85
= 0.15
Yes ordering a soft drink is independent of ordering a square pizza.
We have given 50 percent of the customers at Pizza Palooza order a square pizza, 70 percent order a soft drink, and 35 percent order both a square pizza and a soft drink.
Let A: denote pizza
B: Soft drink
Then,
P(A)=0.5 and P(B)=0.7
And P(A∩B) = P(A) × P(B)
= 0.5 × 0.7
= 0.35
We know P(A∪B) = P(A) + P(B) - P(A∩B)
= 0.5 + 0.7 - 0.35
= 0.85
P(AΔB) = P(A) + P(B) - 2P(A∩B)
= 0.5 + 0.7 - 2×0.35
= 0.5
Also we know P(A') = 1 - P(A)
= 1 - 0.5
= 0.5
And P(B') = 1 - P(B)
= 1 -0.7
= 0.3
And P((A∪B)') = 1 - P(A∪B)
= 1 - 0.85
= 0.15
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What type of triangle has side lengths 9, 10, and √130? A. obtuse B. not a triangle C. acute D. right
Answer: Option C.
Step-by-step explanation:
The lengths of our triangle are:
9, 10 and √130.
If the triangle is a triangle rectangle, by the Pitagoream's theorem we have:
A^2 + B^2 = H^2
in this case H is the larger side, this must be √130.
then:
A and B must be 9 and 10.
9^2 + 10^2 = (√130)^2
81 + 100 = 130
This is false, so this is NOT a triangle rectangle, the hypotenuse is shorter than it should be.
Now, we have some kind of rule:
if A^2 + B^2 = H^2 then we have one angle of 90° and two smaller ones. (triangle rectangle)
if A^2 + B^2 > H^2 then all the angles are smaller than 90°, this is an acute triangle.
if A^2 + B^2 < H^2 then we have one angle larger than 90°, this is an obtuse angle.
(H is always the larger side, A and B are the two shorter ones).
In this case:
81 + 100 > 130
Then this must be an acute angle.
