Please Help
2007-12-05 13:51:08 · 12 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
(3x -- 4y)(3x + 4y) = (3x)^2 -- (4y)^2 = 9x^2 -- 16y^2
2007-12-05 13:53:36 · answer #1 · answered by sv 7 · 1⤊ 0⤋
9x^2 - 16y^2
FOIL stands for first, outer, inner, last.
First pair is 3x * 3x = 9x^2
Outer pair is 3x * 4y = 12xy
Inner pair is -4y * 3x = -12xy
Last pair is -4y * 4y = -16y^2
Add them all together and 12xy - 12xy = 0, so the remaining terms are the answer.
2007-12-05 21:55:35 · answer #2 · answered by Etsap 1 · 0⤊ 0⤋
3X times 3X + 3X times 4Y + -4Y times 3X + -4Y times 4Y
9Xsquared + 12 XY + -12XY + -16Y squared
=9X squared - 16Y squared
2007-12-05 21:55:23 · answer #3 · answered by Joseph Dan 2 · 0⤊ 0⤋
first u multiply 3x by 3x u then get 3x squared then u multiply -4y by 4y which is -4y squared
so..... 3x*2 -4y *2
*= exponent
2007-12-05 21:54:45 · answer #4 · answered by Anonymous · 0⤊ 0⤋
I am not sure what the question is asking, but:
(9x>2<-16y)
The >2< means squared
2007-12-05 21:55:07 · answer #5 · answered by Petunia 2 · 0⤊ 0⤋
Foil it out
9x^2-16y^2
2007-12-05 21:53:59 · answer #6 · answered by ひいらぎ 5 · 1⤊ 0⤋
9x^2-16y^2
just multply each # by every other #. You would get 12xy and -12xy but they cancel each other out so you are left with the answer
2007-12-05 21:57:24 · answer #7 · answered by Anonymous · 0⤊ 0⤋
Use the FOIL method. 9x^2-16y^2 --answer
2007-12-05 21:54:48 · answer #8 · answered by Jewel 1 · 0⤊ 0⤋
3x*3x=9x^2
-4y*3x=-12xy
3x*4y=12xy
-4y*4y=-16y^2
9x^2-16y^2
2007-12-05 21:58:57 · answer #9 · answered by Dave aka Spider Monkey 7 · 0⤊ 0⤋
9x^2+12xy-12xy-16y^2
9x^2-16y^2
2007-12-05 21:54:46 · answer #10 · answered by Zach F 2 · 0⤊ 0⤋