SOLUTION: Solve: 28+5a-12a^2=0 Using factoring and property of 0 we are suppose to solve this problem. I can factor but when I get the finding the answer I get stuck

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: Solve: 28+5a-12a^2=0 Using factoring and property of 0 we are suppose to solve this problem. I can factor but when I get the finding the answer I get stuck      Log On


   



Question 520997: Solve: 28+5a-12a^2=0
Using factoring and property of 0 we are suppose to solve this problem. I can factor but when I get the finding the answer I get stuck

Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
Solve: 28+5a-12a^2=0
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First thing to do is rewrite the equation in decending order
-12a^2+5a+28=0
Get rid of a negative lead coefficient by multiplying both sides of equation by -1
12a^2-5a-28=0
This doesn't look very easy to factor, so consider using the quadratic formula to solve.
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
If you are good at factoring, the answers are:
(3a+4)(4a-7)=0
a=-4/3
or
a=7/4