Question

Solve this x2 – 8x + 15

Answer 1

x=5 or x=3

Explanation:

find two numbers that add up to the middle number (-8) and multiply to equal the last number (15)

in this case -5 and -3 add to be -8 and multiply to be 15

add these numbers in place of -8x

x^2-5x-3x+15 now add parentheses

(x^2-5x) (-3x+15) take out common factors

(x-5)(x-3) now make each set of parentheses equal to zero

x-5=0 x-3=0 now solve

x=5 x=3

Answer 2

x=5 x=3

Explanation:

x^2 – 8x + 15

What two numbers multiply to 15 and add to -8

-5*-3 = 15

-5 +-3 = -8

(x-5) (x-3) =0

Using the zero product property

x-5 =0 x-3 =0

x=5 x=3