factor completely 3tcubed + 5tsquared -12t

Question

factor completely 3t³  + 5t² - 12t

Answer 1

Hi Brandon;

3t³ + 5t² - 12t

 

 

t(3t²+5t-12)

To FOIL 3t²+5t-12....

FIRST...(3t)(t)

LAST...either (-4)(3) or (4)(-3) or (6)(-2) or (-6)(2) or (12)(-1) or (-12)(1)

 

t(3t-4)(t+3)

 

FOIL...(3t-4)(t+3)...

FIRST...3t(t)

OUTER...(3t)(3)=9t

INNER...(-4)(t)=-4t

LAST...(-4)(3)

3t²+9t-4t-12

3t²+5t-12

 

 

 

 

Answer 2

Hi,

You need to understand the process and solve it yourself.

Here is the method:

1. Is there any common factor ? Yes, it is "t". Your job is factor "t" out from that.

2. What is the left over? In that left over part , you see any familiar thing about quadratic factorization when a = 3. If you realize that, the problem is solved. If not, read your notes (textbook) about quadratic factorization when a # 1.

Hope it helps.

Quan.