Question

Sarah is solving for X by the process of completing the square for the following problem..

2x^2+16x-12=0

She got to this point below - type the number that goes in the (?) spot

(x+?)^2=22

Answer 1

4

Explanation:

x²+2(x)(?)+?²=22

multiply by 2 because the coefficient of the higher degree in the first equation is 2

2x²+2(2(x)(?))+2(?²)-2(22)=0

2x²+4x(?)+2?²-44=0

Comparison

4x(?)=16x

?=4

2?²-44=-12

So, 2?²=-12+44

2?²=32

?²=16

?=4

Answer 2

Answer:4

Step-by-step explanation: Since she did it by completing the square, then you must do the same thing to get the same form so you can see what that number is.

So first subtract the constant which is -12 so we need to add twelve to get the constant on the other side. So we now have 2x^2+16x=12

The constant of the x^2 must be 1 so we need to divide by 2 on every term to get x^2+8x=12

So to make it so to get a perfect factor we need to divide the x factor by 2 so we get 4.

So the answer is 4 cause it is a perfect factor so were going to get 4 on both factors.