Question

Omar grouped the terms and factored the GCF out of the groups of the polynomial 3x3 – 15x2 – 4x + 20. His work is shown.

Step 1: (3x3 – 15x2) + (–4x + 20)

Step 2: 3x2(x – 5) + 4(–x + 5)
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Omar noticed that he does not have a common factor. Which accurately describes what Omar should do next?

A Omar should realize that his work shows that the polynomial is prime.

B Omar should go back and regroup the terms in Step 1 as (3x3 – 15x2) – (4x + 20).

C In Step 2, Omar should factor only out of the first expression.

D Omar should factor out a negative from one of the groups so the binomials will be the same.

Answer 1

Yes i believe the right should be D i had asked my teacher this and she said that D was the correct answer have a very nice day my friend 

Answer 2

D) Omar should factor out a negative from one of the groups so the binomials will be the same.

Explanation:

When Omar factored both the groups in step 2 the terms inside the parenthesis were not the same .There was a sign difference .In the next step he should take out a negative from one of the groups then the terms inside the parenthesis will become same .

Step 1:
`(3x^(3) -15x^(2)) +(-4x+20)`

step 2:
`3x^(2) (x-5)+4(-x+5)`

Step 3:
`3x^(2) (x-5)-4(x-5)`