Question

One of the solutions to x2 - 2x – 15 = 0 is x = -3. What is the other solution?

Ox=-5
Ox= -1
0 x=1
x = 5

Answer 1

x=5

Explanation:

Factoring x2 - 2x – 15 we get

(x+3)(x-5) so x+3=0 and x-5=0 or x=-3 and x=5

Answer 2

x=5

Explanation:

x^2 - 2x – 15 = 0

Factor

What 2 numbers multiply to -15 and add to -2

-5*3 = -15

-5+3 = -2

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

Using the zero product property

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

x-5+5 =0+5 x+3-3 = 0-3

x=5 x=-3