Question

3n^2 + 4n - 20 = 0

Solve by factoring, need work shown.

Answer 1

Explanation:

3n^2+4n+20

Let's do group factoring.

First, multiply the leading coefficient by the constant and find a combination that satisfies 4n.

3*20=60 3*20, 10*6

10*6 satisfies 4n since 10-6=4

So

3n^2+10n-6n+20 Group

(3n^2+10n)(-6n+20) Take out the greatest common factor in each section.

n(3n+10)-2(3+10) Combine like terms

(n-2)(3n+10)

To find n make each equation equal zero

n-2=0 Add 2 to both sides

n=2

3n+10=0 Subtract 10 from both sides

3n=-10 Divide both sides by 3

n= -10/3