What are the solutions of the equation (x + 2)2 – 2(x + 2) – 15 = 0? use u substitution to solve.
x = –7 and x = 1
x = –5 and x = 3
x = –3 and x = 5
x = –1 and x = 7

we have

Let

Substitute

Group terms that contain the same variable, and move the constant to the opposite side of the equation

Complete the square. Remember to balance the equation by adding the same constants to each side.

Rewrite as perfect squares

square root both sides

Find the solutions for the variable x

remember that

For

For

therefore

the answer is the option

x = –5 and x = 3

option 3 . (5x + 1) - (-10x + 6)

step-by-step explanation:

option 1 :

(4x + 3) + (-9x + 4)

or 4x+3 -9x + 4

or -5x + 7

option 2

(x - 2) - (6x - 9)

or x-2-6x + 9

or -5x + 7

option 3

(5x+ + 6)

or 5x + 1 + 10x -6

or 15x -5

option 4

-4x+2x+7-3x

-7x + 2x + 7

-5x + 7

hence only option 3 did   not satisfy the given simplify expression.