Answer:
x = 5
or
x = 3
Step-by-step explanation:
The first term is, x2 its coefficient is 1 .
The middle term is, -8x its coefficient is -8 .
The last term, "the constant", is +15
Step-1 : Multiply the coefficient of the first term by the constant 1 • 15 = 15
Step-2 : Find two factors of 15 whose sum equals the coefficient of the middle term, which is -8 .
-15 + -1 = -16
-5 + -3 = -8