Answer: x = -3, -5
Explanation:
Solve by Factoring
x^2 + 8x + 15 = 0
Factor x2 + 8x + 15 using the AC method.
Consider the form x2 + bx + c. Find a pair of i ntegers whose product is c and whose sum is b. In this case, whose product is 15 and whose sum is 8.
3, 5
Write the factored form using these integers.
(x + 3) (x + 5) = 0
If any individual factor on the left side of the equation is equal to 0, the entire expression will be equal to 0.
x + 3 = 0
x + 5 = 0
Set x + 3 equal to 0 and solve for x.
Set x + 3 equal to 0.
x + 3 = 0
Subtract 3 from both sides of the equation.
x = −3
Set x + 5 equal to 0 and solve for x.
Set x + 5 equal to 0.
x + 5 = 0
Subtract 5 from both sides of the equation.
x = −5
The final solution is all the values that make (x + 3) (x + 5) = 0 true.
x = −3, −5