Question

What number must you add to complete the square and then factoring x^2+4x=7

Answer 1

+ 4

Explanation:

given

x² + 4x = 7

To complete the square

add ( half the coefficient of the x- term )² to both sides

x² + 4x + (
`(4)/(2)`)² = 7 + (
`(4)/(2)`)², that is

x² + 4x + 4 = 7 + 4

(x + 2)² = 11

Answer 2

The number 4 must add to complete the square

(x + 2)^2 = 11

Explanation:

The given quadratic equation is, x^2 + 4x = 7

For completing square,

We have to add square of half of the coefficient of x.

Here coefficient of x is 4

Half of coefficient of x = 4/2 = 2

Square of half of coefficient of x = 2^2 = 4

We have to add 4 on both side

Therefore the answer is 4

Factoring x^2 + 4x = 7

Add 4 on both side we get,

x^2 + 4x + 4 = 7 + 4

(x + 2)^2 = 11