Question

Need help with factoring trinomial's!

Answer 1

\[a ^{2} - a - 20\]

Answer 2

can you find 2 numbers with product = -20 and sum =-1 ??

Answer 3

-5 & 4?

Answer 4

-5*4 = -20
-5 + 4 = -20

Answer 5

Right?

Answer 6

thats correct!
so, split -a as -5a +4a
we have , \(a^2 -5a+4a-20=0\)
factor out a from first 2 terms and 4 from last 2 terms , what u get ?

Answer 7

Ummm

Answer 8

Not sure . . .

Answer 9

Wouldn't you just leave it as -5 & 4?

Answer 10

\(a^2-5a = a (a-5)\)
looks good ?

Answer 11

no...

Answer 12

Ok . . . I guess that looks good

Answer 13

Thanks

Answer 14

4a-20 =4(...?.. )

Answer 15

i wasn't done yet :P

Answer 16

Utterly confused . . .

Answer 17

\(a^2-5a+4a-20 = a(a-5)+4(a-5)\\=(a-5)(a+4)\)
now factoring is complete

Answer 18

Ok . . .