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.
