SOLUTION: solve by factoring x cubed-9x=0 y squared-2y-24=0

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Question 106565: solve by factoring
x cubed-9x=0
y squared-2y-24=0
Found 2 solutions by edjones, ashlyn.xo:
Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
x^3-9x=0
x(x^2-9)=0
x(x+3)(x-3)=0
x=0, x=-3, x=3
.
y^2-2y-24=0
(y-6)(y+4)=0
y=6, y=-4
.
Ed

Answer by ashlyn.xo(7) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E3-9x=0
this equation cannot be factored, because there is no square root of x%5E3



y%5E2-2y-24=0
GAME: think of 2 numbers that is the product to the 3rd term (-24) and the sum of the 2nd term (-2).
These two numbers would be: -6,4
This is because: -6%2A4=-24
And: -6%2B4=-2
now, substitute these two numbers as the middle term in the equation:
y%5E2-6y%2B4y-24=0
Now, common factor by GROUPING
-Common Factor the first two terms
-Common factor of y%5E2-6y is y
-Common Factor the last two terms
-Common factor of 4y-24 is 4
Therefore, the equation is now y%28y-6%29%2B4%28y-6%29=0 after dividing by the common factors.
Take the equation y%28y-6%29%2B4%28y-6%29=0 and common factor again, this time the common factor being (y-6)
Therefore, %28y-6%29%2A%28y-4%29=0