Question

Some for all values of x by factoring

Answer 1

{-1,10}

Explanation:

`x^2-9x-15=-5` given

`x^2-9x-10=0` addition property of equality

`x^2+(x-10x)-10=x^2+x-10x-10=0` x-10x = -9x

`x(x+1)-10(x+1)=0` distributive property ( x( y + z ) = xy + xz

`(x-10)(x+1)=0` distributive property (backwards)

`x-10=0;x=10;x+1=0;x=-1` at least one factor of 0 has to be 0

{-1,10}

Answer 2

{-1, 10}

Explanation:

Next time please share the entire set of instrutions.

x^2 - 9x - 15 = -5 should be rewritten in standard quadratic form:

x^2 - 9x - 10 = 0 = (x - 10)(x + 1) = 0.

Setting each factor equal to zero and then solving for x yields {-1, 10}