SOLUTION: Here are a few problems that I am grindin my teeth at: Factor completely: 3a^2 - 27b^2 would the answer be 3(a * a) - (3 * 3* 3)(b * b)? # 2 x^2 - 15wy + 3xy - 5 wx woul

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: Here are a few problems that I am grindin my teeth at: Factor completely: 3a^2 - 27b^2 would the answer be 3(a * a) - (3 * 3* 3)(b * b)? # 2 x^2 - 15wy + 3xy - 5 wx woul      Log On


   



Question 43060: Here are a few problems that I am grindin my teeth at:
Factor completely:
3a^2 - 27b^2
would the answer be 3(a * a) - (3 * 3* 3)(b * b)?
# 2 x^2 - 15wy + 3xy - 5 wx
would it be (x8x) - (3*5wy) + 3xy - 5 wx?
# 3
9x^2 - 36y^2
would it be (3*3)(x*x) - 3*3*2*2(y*y)?
# 4
3x^2 + 2x - 8
would it be 5 (x*x + x) -8

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Factor completely:
3a%5E2+-+27b%5E2
factor out 3
3%28a%5E2+-+9b%5E2%29
both terms in paren are perfect squares, a%2Aa+=+a%5E2, 3b%2A3b+=+9b%5E2
so, use the rule that %28x%5E2+-+y%5E2%29+=+%28x+-+y%29%28x+%2B+y%29
3%28a%2B+3b%29%28a+-+3b%29 answer
----------------------
2x%5E2+-+15wy+%2B+3xy+-+5+wx
this is a tough one. The best I can come up with is this
x%5E2+%2B+x%5E2+-+15wy+%2B+3xy+-+5+wx
x%5E2+%2B+x%28x+%2B+3y%29+-+5w%28x+%2B+3y%29
factor out (x + 3y)
x%5E2+%2B+%28x+%2B+3y%29%28x+-+5w%29 answer, but I'm not sure
------------------------
9x%5E2+-+36y%5E2
both terms are perfect squares, 9x%5E2+=+3x%2A3x, 36y%5E2+=+6y%2A6y
%283x+%2B+6y%29%283x+-+6y%29 answer
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3x%5E2+%2B+2x+-+8
this is not hard, just have to puzzle it out
The factors of 3x%5E2 are 3x and x
(3x - ?)(x + ?)
I tried
(3x - 2)(x + 4)
that equals
3x%5E2+%2B10x+-6 wrong
then
(3x - 4)(x + 2) BINGO answer
3x%5E2+%2B+2x+-+6