Question

Factor out the GCF, then solve the following expression.

3x² + 21x = 0
A {0, 24}
B {-7, 3}
C {0, 7}
D {-7, 0}

Answer 1

D {-7, 0}

Explanation:

The GCF is 3x

3x(x+7) = 0

x = {-7, 0}

Answer 2

D {-7, 0}

Explanation:

3x^2 = 3*x*x

21x = 3*7*x

The greatest common factor is 3x

3x(x+7) =0

Using the zero product property

3x=0 x+7 =0

x=0 x+7-7 =0-7

x=0 x=-7