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3 years ago

Use completing the square to solve for x in the equation (x-12)(x+4)= 9.

Mathematics

1 answer:

iragen [17]3 years ago

4 0

Answer:

x = 4 + sqrt(73) or x = 4 - sqrt(73)

Step-by-step explanation by completing the square:

Solve for x:

(x - 12) (x + 4) = 9

Expand out terms of the left hand side:

x^2 - 8 x - 48 = 9

Add 48 to both sides:

x^2 - 8 x = 57

Add 16 to both sides:

x^2 - 8 x + 16 = 73

Write the left hand side as a square:

(x - 4)^2 = 73

Take the square root of both sides:

x - 4 = sqrt(73) or x - 4 = -sqrt(73)

Add 4 to both sides:

x = 4 + sqrt(73) or x - 4 = -sqrt(73)

Add 4 to both sides:

Answer: x = 4 + sqrt(73) or x = 4 - sqrt(73)

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2 years ago

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2 years ago

How many acres of land are in a rectanglar parcel 234' * 878'

uysha [10]

An acre is 43,560 ft² because the customary system hates you.

Let's find out how many square feet the parcel is so we can convert it into acres.

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A ≈ <span>4.7165 acres. (round as needed)</span>

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2 years ago

a container of candy is shaped like a cylinder and has a volume of 125.6 cubic centimeters. If the heights of the container is 1

Elenna [48]

The radius of the container is 2 centimeter

<h3><u>Solution:</u></h3>

Given that a container of candy is shaped like a cylinder

Given that volume = 125.6 cubic centimeters

Height of conatiner = 10 centimeter

To find: radius of the container

We can use volume of cylinder formula and obatin the radius value

<em><u>The volume of cylinder is given as:</u></em>

$\text {volume of cylinder }=\pi r^{2} h$

Where "r" is the radius of cylinder

"h" is the height of cylinder and $\pi$ is constant has value 3.14

Substituting the values in formula, we get

$\begin{array}{l}{125.6=3.14 \times r^{2} \times 10} \\\\ {r^{2}=\frac{125.6}{31.4}} \\\\ {r^{2}=4}\end{array}$

Taking square root on both sides,

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2 years ago

Please help asap 25 pts

beks73 [17]

$y=ax^2+bx+c\\\\\text{Axis of symmetry:}\ x=\dfrac{-b}{2a}$

$\text{We have:}\\\\y=4x^2+16x-18\\\\a=4;\ b=16;\ c=-18\\\\x=\dfrac{-16}{2\cdot4}=\dfrac{-16}{8}=-2$

Answer: A.

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2 years ago