3.) What are the solutions to x^2 + 8x + 7 = 0?

x = - 8 and x = - 7

x = - 7 and x = - 1

x = 1 and x = 7

x = 7 and x = 8

Check if x = - 8 is the solution

1. substitute number - 8 for x in the equation

(-8) ^2 + 8 * (-8) + 7 = 0

2. do calculations on the left size

64 - 64 + 7 = 0

7 = 0

3. equality means x is the solution, inequality means it is not

-8 is not the solution to x^2 + 8x + 7 = 0

check other given numbers the same way

x=-7

(-7) ^2 + 8 * (-7) + 7 = 0

0=0

-7 is the solution

x=-1

(-1) ^2 + 8 * (-1) + 7 = 0

0=0

-1 is the solution

x=1

(1) ^2 + 8 * (1) + 7 = 0

16=0

1 is not the solution

x=7

(7) ^2 + 8 * (7) + 7 = 0

113=0

7 is not the solution

x=8

(8) ^2 + 8 * (8) + 7 = 0

135=0

8 is not the solution

answer:

The solutions to given equation are - 7 and - 1.

The answer to this question is

-7+-1=-8

-1+-7=8

1+7=8