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3 votes
4x3 + 12x2 = 40x
How to solve by factoring

User Raphnguyen
by
7.3k points

2 Answers

1 vote

Answer:0.9

Explanation:

4x3+12x2=40X

12+24=40x

36=40x

x=36 ➗ 40

x=0.9

User Crowder
by
7.7k points
6 votes

Answer:

x=0 x=-5 x=2

Explanation:

4x3 + 12x2 = 40x

Subtract 40x from each side

4x3 + 12x2 - 40x=0

Factor out 4x from each term

4x( x^2 +3x-10) =0

Factor the term insdie the parentheses

What 2 numbers multiply to -10 and add to 3

5*-2 =-10

5+-2 =3

We have (x+5) (x-2)

Replace that in the equation

4x ( x+5) (x-2) =0

Using the zero product property

4x= 0 x+5 =0 x-2 =0

x=0 x=-5 x=2

User Gang YIN
by
7.4k points