Solve x2 + 20x + 100 = 36 for x. Use completing the sqaure

1 answer:

7 0

X^2+20x+100=36
-subtract 100 and move to other side
x^2+20x____=36-100
-divide 20 by 2 which gives you 10.
-square 10= (10)^2 which gives you 100.
-add the 100 to the right side of the equation.
(x+10)^2 = 36-100+100
(x+10)^2=36
-cancel out the square root and square root 36
(x+10)= 6
-subtract 10
x=-4

*Plug in (-4) into the equation to check your work*

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Option:

a. for every 13 dogs, there are 25 cats.

b. there are twice as many cats as dogs at the shelter.

c. the shelter has more dogs than cats.

d. there are 25 animals in the shelter.

Answer:

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Step-by-step explanation:

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By comparison:

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mylen [45]

Answer:

x = 1.19258 and x = −4.19258

Step-by-step explanation:

The given equation is :

$x^2+3x-5=0$

Keep x terms on the left and move the constant to the right side by adding it on both sides.

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Take half of the x term and square it.

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then add the result to both sides

$x^2+3x+\dfrac{9}{4}=5+\dfrac{9}{4}\\\\(x+\dfrac{3}{2})^2=\dfrac{29}{4}\\\\(x+\dfrac{3}{2})=\sqrt{\dfrac{29}{4}}\\\\x=\dfrac{-3}{2}+\sqrt{\dfrac{29}{4}}\\\\x=\dfrac{-3}{2}-\sqrt{\dfrac{29}{4}}$