Answers
Answer:
This is called "completing the square"
It is a technique to solve a quadratic equation. It involves "moving all
of the constants to the right" , then doing a "move" on the left hand side. This move "creates a perfect square".. This is done by taking 1/f of the "B" term and squaring it... this will "un-balance" the sides of the equation... to balance it out you have to "add" some stuff to the right hand side... when done the left side will be "a perfect square" .. last step will be take the square root of both sides.
Step-by-step explanation:
[tex]x^2 + 12x + 15 = 0[/tex]
[tex]x^2 + 12x + 15 -15 = -15[/tex]
[tex]x^2 + 12x = -15[/tex]
[tex]b = 12 ... (1/2 b)^2 = 6^2 = 36[/tex]
[tex]x^2 + 12x + 36 = -15 + 36[/tex]
[tex]x^2 + 12x + 36 = 21[/tex]
[tex](x+ 6)^2 = 21[/tex]
[tex]\sqrt{(x+ 6)^2 } =[/tex] ± [tex]\sqrt{21}[/tex]
[tex]x+ 6[/tex]= ± [tex]\sqrt{21}[/tex]
x = -6 ±[tex]\sqrt{21}[/tex]
Answer:
Step 1: -15
Step 2: b = 12, c = 36
Step 3-4: x² + 12x + 36 = -15 + 36, which simples to (x + 6)² = 21
If there is a step that has you solve for x, it should be -6 + √21 or -6 - √21.
Step-by-step explanation:
Step 1 is pretty simple. All we have to do is subtract 15 from 0 to get the first blank.
x² + 12x = 0 - 15
x² + 12x = -15
Step 2:
b is the coefficient on x, which is 12.
Then, use the formula mentioned:
[tex]c = ( \frac{b}{2})^{2} \\ c = ( \frac{12}{2} )^{2} \\ c ={6}^{2} \\ c = 36[/tex]
As a result of that, c is 36.
Now to substitute and simplify. (Steps 3-4)
x² + 12x + 36 = -15 + 36
To factor an equation, think about it like this: Find two numbers that add to the coefficient of x, and multiply to the constant. So what two numbers add to 12, and multiply to 36? That would be 6 & 6 (6 + 6 = 12; 6 × 6 = 36).
(x + 6)² = -15 + 36
Add 36 to -15 to get 21.
(x + 6)² = 21
That should solve steps 1-4, but I will go on ahead and give the final answer to the entire problem.
(x + 6)² = 21
Yes, you are about see what I just factored be expanded back over again. It's part of the process.
x² + 12x + 36 = 21
Now subtract 21 from both sides.
x² + 12x + 36 - 21 = 21 - 21
x² + 12x + 15 = 0
Now onto the hard part of this: the quadratic formula. a = (the understood) 1, b = 12, and c = 15.
x = (-b ± √b² - 4ac)/2a
x = -12 ± √12² - 4(15)/2
x = -12 ± √144 - 60/2
x = -12 ± ✓84/2
x = -6 + √21 or -6 - √21
Related Questions
The freezing point of oxygen is –218.790C and hydrogen is –252.80C. A lab is lowering the temperature inside a fridge. Which freezes first? How much colder does it have to be for both to freeze?
Answers
Answer:
Oxygen; 34.01°C
Step-by-step explanation:
The oxygen freezes first as it has a higher (warmer) freezing point. For both to freeze, the temperature must drop a further 34.01°C as:
-218.79 - (-252.8)
= 252.8 - 218.79
= 34.01
Lusine saw birds and mice eating seeds on the ground. She calculated 12 heads and 39 legs in total. How many birds and mice are on the ground?
Answers
Answer:
4.5 birds, 7.5 mice
Step-by-step explanation:
We know that birds have 2 legs and mice have 4. Furthermore, birds have 1 head as well as mice.
If b represents the amount of birds and m represents the amount of mice, because there are only birds and mice here, the total amount of birds and mice (b + m) must equal 12.
b + m = 12
Next, to find the total amount of bird legs, we must add 2 legs for each bird. Another way of putting this is to multiply 2 by the amount of birds, or b * 2. Similarly, the amount of mice legs is equal to m * 4. The total amount of legs is equal to 39, so
2b + 4m = 39
Our two equations are thus
b + m = 12
2b + 4m = 39
One way to solve this is to solve for m in the first equation and plug that into the second. We have
b + m = 12
subtract b from both sides
m = 12-b
substitute that into the second equation
2b + 4(12-b) = 39
2b + 48 - 4b = 39
-2b + 48 = 39
subtract 48 from both sides to isolate the b and its coefficient
-2b = -9
divide both sides by -2 to isolate b
b = 4.5
Therefore, there are 4.5 birds on the ground (there is somehow a half of a bird!)
Plugging that into m = 12-b, we have m = 12-4.5 = 7.5
2. What is the area of rhombusABCD? (Assume the diagonals of rhombus ABCD are equal).
Answers
Answer:
A=pq/2
=4.25·4.25/2
=9.03125
Step-by-step explanation:
If you like my answer than please mark me brainliest
Answer:
Step-by-step explanation:
Diagonal of rhombus bisect each other.
d₁ = AC = 4.25*2 = 8.5 cm
d₂ = 8.5 {Given diagonals are equal}
Area of rhombus = [tex]\frac{d_{1}*d_{2}}{2} \ where \ d_{1} \ and \ d_{2} \ are \ diagonals[/tex]
[tex]=\frac{8.5*8.5}{2}\\\\= \frac{72.25}{2}\\\\= 36.125 \ cm^{2}[/tex]
What must be added to each term of the ratio 2:5 so that it maay be equal to 5:6
please explanation needed
Answers
Let the adding value be x
ATQ
[tex]\\ \sf\longmapsto \dfrac{2+x}{5+x}=\dfrac{5}{6}[/tex]
[tex]\\ \sf\longmapsto 6(2+x)=5(5+x)[/tex]
[tex]\\ \sf\longmapsto 12+6x=25+5x[/tex]
[tex]\\ \sf\longmapsto 6x-5x=25-12[/tex]
[tex]\\ \sf\longmapsto x=13[/tex]
On Monday a post office employee processed a batch of letters, on Tuesday she processed three times as many, and on Wednesday she processed 5,000 cards. In the 3 days she processed 15,000 letters. How many did she process on Tuesday
Answers
Let the number of letters processed on Monday = x
She processed 3 times letters on Tuesday.
Therefore, number of letters processed on Tuesday = 3x
Number of letters processed on Wednesday = 5000
Total number of cards processed in 3 days = 15000
Therefore, equation for the situation will be,
x + 3x + 5000 = 15000
4x = 15000 - 5000
4x = 10000
x = 2500
Since, number of letters processed on Tuesday = 3x
Therefore, number of letters processed on Tuesday = 3(2500)
= 7500
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Help anyone can help me do the question,I will mark brainlest.
Answers
Step-by-step explanation:
h) p^2+b^2=h^2
5^2+x^2=8^2
25+x^2=64
x^2=64-25
x^2=39
x=√39
x=6.244998
We know that
p² + b² = h²
Part a
5² + x² = 8²
x² = 64 - 25
x = √39
Part B
4² + 6² = x²
16+36 = x²
√52 = x
√2×2×13 = x
x = 2√13
Must click thanks and mark brainliest
The cost,c(x), for a taxi ride is given by c(x)=3x+2.00, where x is the number of minutes. What does the slope mean for this situation
Answers
Answer:
for every minute it will cost 3 dollars
Step-by-step explanation:
c(x)=3x+2.00
The cost to get in the taxi is 2 dollars
The slope is 3
3x means that for every minute it will cost 3 dollars
7+3√5/3+√5 - 7-3√5/3-√5
Answers
Answer:
0
Step-by-step explanation:
We can write the equation in a simpler form so it doesn't look like a mess of numbers:
[tex]7+\frac{3\sqrt{5}}{3}+\sqrt{5} -7 -\frac{3\sqrt{5}}{3}-\sqrt{5}[/tex]
Because we are just adding three terms together and then subtracting those exact terms, we have the answer as 0.
10 points please help im confused
What is the volume of the prism?
103.8 cubic inches
114.9 cubic inches
140.6 cubic inches
110.5 cubic inches
Answers
Answer:
110.5 cubic inches
Step-by-step explanation:
Base is parallelogram, so area is
A = 4.7×5 = 23.5
Height(h) is 4.7, so volume is,
V = A×h
= 23.5×4.7
= 110.45 ≈ 110.5
Answered by GAUTHMATH
Which equation is equivalent to -2(2 − 2x) = 4 − 8(1 − x)?
Answers
Answer:
x = 0
Step-by-step explanation:
-2(2 − 2x) = 4 − 8(1 − x)
Apply the distributive property:
−2(2 − 2x) = 4 − 8(1 − x)
(−2)(2) + (−2)(−2x) = 4 + (−8)(1) + (−8)(−x)
−4 + 4x = 4 + (−8) + 8x
Combine like terms:
4x − 4 = (8x) + (4+−8)
4x − 4 = 8x + (−4)
4x − 4 = 8x − 4
Subtract 8x from both sides:
4x − 4 − 8x = 8x − 4 − 8x
−4x − 4 = −4
Add 4 to both sides:
−4x − 4 + 4= −4 + 4
−4x = 0
Divide both sides by -4:
-4x/-4 = 0/-4
x = 0
Answer: 0
Step-by-step explanation:
Find the measure of side C and round to the nearest whole number. Pls help ASAP
Answers
Answer:
Step-by-step explanation:
Side a is across from angle A, and side c is the hypotenuse. The trig ratio that utilizes the side opposite and the hypotenuse is the sin of an angle, namely:
[tex]sin(30)=\frac{28}{c}[/tex] and solving that for c:
[tex]c=\frac{28}{sin(30)}[/tex] so
c = 56
The formula for the lateral surface area of a cone—that’s the surface that isn’t the base—is π × r × sqrt(h² + r²); h is the height of the cone and r is the radius of its base. A circular #2 pencil is 6 mm in diameter, and a pencil sharpener creates a cone-shaped end that is 20 mm in height. Find the surface area of the sharpened part of the pencil.
Answers
slove the equation for y and x
Answers
Answer:
x=2
y=-3
Step-by-step explanation:
2x+y = 1
3x+2y = 0
Multiply the first equation by -2
-4x-2y = -2
Add this to the second equation
-4x-2y = -2
3x+2y = 0
-------------------
-x = -2
Multiply by -1
x = 2
Now find y
2x+y = 1
2(2) +y = 1
4 +y = 1
Subtract 4 from each side
y = 1-4
y = -3
Answer: y = -2x + 1
Solution to the system: (2,-3)
Step-by-step explanation:
2x + y = 1
3x + 2y = 0
We can solve this using substitution
The first thing that we're going to want to do is solve for y in the first equation
Solve for y
2x + y = 1
Subtract 2x from both sides
y = 1 - 2x
We now have the two equations
y = -2x + 1 and 3x + 2y = 0
The next step in solving the system is to plug in the expression of y ( -2x + 1) into the second equation
3x + 2y = 0
Substitute -2x + 1 for y
3x + 2(-2x + 1) = 0
Now solve for x
Distribute the 2 to the -2x and 1
2 * -2x = -4x
2 * 1 = 2
We now have 3x - 4x + 2 = 0
Combine like terms
-x + 2 = 0
Add x to both sides
2 = x
Now to find the value of y we substitute the value of x into one of the equations and solve for y
2x + y = 1
x = 2
2(2) + y = 1
Multiply
4 + y = 1
Subtract 4 from both sides
y = -3
The solution to the system is (2,-3)
And we are done!
cherly gets paid $8 per hour at her job at the record store. she made a total of $96 last week .write a multiplication equation to show how many hours she worked last week
Answers
Answer:
8(h)=96
Step-by-step explanation:
Remember when you are writing a multiplication equation, it's a division backwards.
96/8=h
h×8=96
hope this helps you
goodluck
Answer: 8x=96
Step-by-step explanation:
8X = 96
X = 96/8
X = 12 hours
someone answer fast with a model: Kevin spends $11.25 on lunch every week during the school year.If there are 35.5 weeks during the school year how much dies Kevin spend on lunch over the entire school year? Remember to round to the nearest penny
Answers
Answer:
$399.45
Step-by-step explanation:
all you gotta do is
11.25×35.5
First, you multiply. You get $399.375. when you round it to the nearest penny, look behind the decimal, see if it's going down to 0, or going higher than 5, then round. the overall answer is going to be..............$399 and 40 cents.
Brainliest 70 Points! Write an equation representing the translation of f(x) = 7x + 3 down 4 units.
Answers
The transformation of a function may involve any change. The function, g(x) that represents function f(x) moved 4 units downwards is g(x)=7x-1.
How does the transformation of a function happen?The transformation of a function may involve any change.
Usually, these can be shifted horizontally (by transforming inputs) or vertically (by transforming output), stretched (multiplying outputs or inputs) etc.
If the original function is y = f(x), assuming horizontal axis is input axis and vertical is for outputs, then:
Horizontal shift (also called phase shift):
Left shift by c units: y=f(x+c) (same output, but c units earlier)Right shift by c units: y=f(x-c)(same output, but c units late)Vertical shift:
Up by d units: y = f(x) + d Down by d units: y = f(x) - dStretching:
Vertical stretch by a factor k: y = k × f(x)Horizontal stretch by a factor k: y = f(x/k)Given the function f(x)=7x+3, now, if the function is moved down by d units, then the function can be transformed down wards by 4 units as shown below.
g(x) = f(x) moved down by 4 units
g(x) = f(x) - 4
g(x) = 7x + 3 - 4
g(x) = 7x - 1
Hence, the function, g(x) that represents function f(x) moved 4 units downwards is g(x)=7x-1.
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lf y 1/4 · when x=5, find y when x=7. given that y varies directly with x.
y=
Answers
Answer:
y= 0.35
Step-by-step explanation:
y 1/4
when x=5,
find y=? when x=7.
given that y varies directly with x.
y = kx
Where k is the constant of proportionality
k= y/x
k= (1/4)÷ 5
k= 0.05
y= kx
y= (0.05)(7)
y= 0.35
I Hope this will helpful...
The perimeter of a rectangular plot of land whose length is (2x+5) and width is (x-10) is 80cm. Find the
i)value of x
ii) area
iii)cost of weeding the plot at GHc 0.24 per m²
Answers
Answer:
P.=2(2x+5)+2(x-10)=80cm
6x-10=80
x=90/6=15cm
Area= L*W= 35*5=175 squared cm= 0.0175 squared m
Cost= 0.24 * 0.0175 = GHc 0.0042
A parallelogram in which adjacent sides are perpendicular to each other is called a rectangle. The cost of weeding the rectangular plot is 0.0042 GHc.
What is a rectangle?That parallelogram in which adjacent sides are perpendicular to each other is called a rectangle. A rectangle is always a parallelogram and a quadrilateral but the reverse statement may or may not be true.
A.) The perimeter of a rectangular plot of land whose length is (2x+5) and width is (x-10) is 80cm. Therefore, we can write,
Perimeter of the rectangel = 2(L+W)
80 = 2[(2x+5)+(x-10)]
80/2 = 2x+5+x-10
40 = 3x -5
40+5 = 3x
x = 15
Hence, the value of x is 15.
B.) The length of the rectangle = (2x+5) = 2(15)+5 = 35 cm = 0.35 m
The width of the rectangle = (x-10) = 15-10 = 5 cm = 0.05 m
Now, the area of the rectangle = L×B = 0.35m × 0.05m = 0.0175m²
C.) Given the cost of weeding 1m² is 0.24, therefore, the cost of weeding the rectangular plot is
Cost = 0.0175 × 0.24 = 0.0042 GHc
Hence, the cost of weeding the rectangular plot is 0.0042 GHc.
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Can A KIND SOUL HELP ME OUT??? ALL THE ANSWERS I SEE ARE WRONG FOR THIS PROBLEM!!!!!!!!!!:(((
Find the measures of angles x, y and z in the figure.
please show how you got it so I can see if the answer makes sense!!!!
Answers
Answer:
x=y=z=106
Step-by-step explanation:
The upper line is a straight line, so x+74=180, x=106.
y and x are equal in measure as it's a pair of parallel lines and z=y as they are alternate interior angles
Evaluate the expression when b= -6.
b^2-6b+4
Answers
-6(-6) = 36
Answer:
76
Step-by-step explanation:
when b = -6
b^2 - 6b + 4
(-6)^2 - 6(-6) + 4
36 + 36 + 4 = 76
(remember, a negative times a negative always equals a positive)
... please mark as brainliest!! :)) ...
What's the angle sum of a polygon having 7 sides.
Answers
Answer:
900°
Step-by-step explanation:
The sum of the interior angles of a polygon is
sum = 180° (n - 2) ← n is the number of sides
Here n = 7 , then
sum = 180° × 5 = 900°
What is the reciprocal of 7/9 it’s a fraction by the way
Answers
Answer:
9/7
Step-by-step explanation:
Reciprocal means 1 over the number
1 / (7/9)
1 * 9/7
9/7
Answer:
[tex] = \frac{9}{7} [/tex]
Step-by-step explanation:
Reciprocal means inverse:
[tex] {( \frac{7}{9} })^{ - 1} = (\frac{9}{7} ) {}^{1} \\ \\ = \frac{9}{7} [/tex]
Which expression is equal to "13 more than the quotient of n and 8"? *
A) 13n + 8
B) n - 8 + 13
C) n * 8 + 13
D) (n / 8) + 13
Answers
Answer:
D
Step-by-step explanation:
The quotient of n and 8 is [tex]\frac{n}{8}[/tex] and 13 more than this is
[tex]\frac{n}{8}[/tex] + 13 → D
If u work it out in PENDAS
First u do () n/8
Then u add 13
Which would make the answer 13 more
The HCF of 85 and 95
Answers
Answer:
So the greatest common factor 85 and 95 is 5.
Step-by-step explanation:
We will now calculate the prime factors of 85 and 95, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 85 and 95.
We will first find the prime factorization of 85 and 95. After we will calculate the factors of 85 and 95 and find the biggest common factor number .
Step-1: Prime Factorization of 85Prime factors of 85 are 5, 17. Prime factorization of 85 in exponential form is:
85 = 5^1 × 17^1
Step-2: Prime Factorization of 95Prime factors of 95 are 5, 19. Prime factorization of 95 in exponential form is:
95 = 5^1 × 19^1
Step-3: Factors of 85List of positive integer factors of 85 that divides 85 without a remainder.
1, 5, 17
Final Step: Biggest Common Factor NumberWe found the factors and prime factorization of 85 and 95. The biggest common factor number is the GCF number.
So the greatest common factor 85 and 95 is 5.
what is the value of x
Answers
Answer: 24(option A) is the answer
exterior angle = 360/n
so, n = 15
then, 360/15 = 24
Simplify. x/4+x/3//x/2
Answers
Answer:
Step-by-step explanation:
[tex]x^2-x-6=0[/tex]
Answers
Answer:
x = 3 or x = -2
Step-by-step explanation:
x² - x - 6 = 0
(x - 3)(x + 2) = 0
x - 3 = 0 or x + 2 = 0
x = 3 or x = -2
Q = (√x-5)² + (√x+4)-41
Answers
Answer:
. .
Step-by-step explanation:
x^2-9x√x-12
solve by using formula (a+b)^2 and open the brackets
The diagram below represents which percent?
An area model with 4 shaded sections and 1 unshaded section.
Answers
Answer:
25%
Step-by-step explanation:
1 ÷ 4 = 0.25
0.25 x 100 = 25 = 25%
Last year 160 new candidates submitted applications to work for an agency. This year, that number is on target to increase by 25%. There are 6 months left in the year. How many new applications has the agency received so far this year?
Answers
Answer:100
Step-by-step explanation:
Given
Last year 160 new candidates submitted to work for agency
It is expected to increase by 25% that is , increase in one year should be
[tex]\Rightarrow 160+160\times 25\%\\\Rightarrow 160(1+0.25)\\\Rightarrow 160\times 1.25\\\Rightarrow 200[/tex]
200 application in the upcoming year. So, in 6 months, agency must have accepted 100 applications.
