Question

a2 – a – 20 Factor each trinomial how do you do this someone explain pleasee

Answer 1

Can you find two numbers that multiply to -20 AND add to -1 at the same time?

Answer 2

yess

Answer 3

what numbers did you find

Answer 4

positve 4 and - 5

Answer 5

so

a^2 - a - 20

factors to

(a + 4)(a - 5)

Answer 6

A bigger breakdown is this


a^2 - a - 20

a^2 + 4a - 5a - 20 .... Notice how 4a - 5a = -a

(a^2 + 4a) + (-5a - 20)

a(a+4) - 5(a+4)

(a - 5)(a + 4)

Answer 7

You can check the answer by going in reverse and expanding that out

Answer 8

thankyou kind sr :)