Question

factor
24a^3b^4-6a^5b^7-21ab^3

I really need help with factoring

Answer 1

\[24a^3b^4-6a^5b^7-21ab^3\]

Answer 2

yesss thats the equation

Answer 3

alright then look at the terms and can you see anything that they all share?

Answer 4

ab??

Answer 5

ok so we pull ab out of the entire expression
\[(ab)24a^2b^3-6a^4b^6-21b^2\]

can you see anything else that they all share?

Answer 6

oops i typed that wrong it should be

Answer 7

\[(ab)(24a^2b^3-6a^4b^6-21b^2)\]

Answer 8

they all share.....?? exponents???/

Answer 9

ok just look at this expression
\[24a^2b^3-6a^4b^6-21b^2\]
ignore the ab for now

and remember your times table for 3

Answer 10

what else does each value in that expression share?

Answer 11

they share multiples of 3

Answer 12

ok what else?

Answer 13

ummmm...? thats all i can think of...

Answer 14

let me remind you that b^5 = b*b*b*b*b
b^2= b*b

Answer 15

ok i got that

Answer 16

and b^5 = b^2*b^3

Answer 17

ok then ill make it more obvious
\[24a^2b^2b-6a^4b^2b^4-21b^2\]

Answer 18

using the distribution property of multiplication, what else can we pull out of this expression?

Answer 19

i don't get why you just did that though...

Answer 20

they all have b^2 in common...

Answer 21

they all have a b

Answer 22

so we pulled out (ab)(3)(b^2)
\[24a^3b^4-6a^5b^7-21ab^3=(3)(ab)(b^2)(8a^2b-2a^4b^4-7)\]
and
\[(3)(ab)(b^2)= 3ab^3\]