Question

Factor completely 2x^2+6x-80

Answer 1

Solution = 2(x-5)(x+8)

Explanation:

1. Common Factor

2(x^2+3x-40)

2. Use Sum Product pattern

2(x^2+8x-5x-40)

3. Common Factor from the two pairs

2(x-5)(x+8)

Answer 2

x= -8 , x=5

Explanation:

2x^2+6x-80=0

x^2+3x-40=0

look for 2 numbers that their:

sum = 3

product = -40

(x+8)(x-5)=0

thus

x= -8 , x=5 (ANS)