could someone help me with this math equation?

Question

Factor the following trinomial completely. Look first for the greatest common factor.

20r⁴-48r³-36r²

Answer 1

Hi Seth,

 

Factor the following trinomial completely. Look first for the greatest common factor.

20r⁴-48r³-36r²

 

 

You have to look for the greatest common factor to all three terms.  First factor the terms.

1st term 20r⁴                 1*2*2*5*r*r*r*r
2nd term -48r³             -1*2*2*2*2*3*r*r*r
3rd term -36r²              -1*2*2*2*2*3*r*r

What factor is common to all three? Looks like 2*2*r*r= 4r²

1st term 20r⁴                1*2*2*5*r*r*r*r                     =4r²  (5r²)
2nd term -48r³            -1*2*2*2*2*3*r*r*r                 =4r²(-12r)
3rd term -36r²             -1*2*2*3*3*r*r                       =4r²(-9)


The 4r² is factored out and what is left goes in the parentheses.

             20r⁴-48r³-36r²

          = 4r²(5r²-12r-9)

 

Now the expression is fully factored.

Hope this helps you with the process of factoring.

THINK MATH!!