Question 236058: If the two solutions of a quadratic equation =-4 and 3 and c=4 then how do I solve this problem and write it in standard form?
Answer by Theo(13342) (Show Source):
You can put this solution on YOUR website! If the roots are x = -4 and x = 3, then the equation would be:
(x+4) * (x-3) = 0
Multiply these factors together to get:
x^2 + x - 12 = 0
Since your c factor has to be 4, then you need to divide both sides of this equation by -3 to get:
-x^2/3 - x/3 + 4 = 0
This would be the same as:
-(1/3)*x^2 - (1/3)*x + 4 = 0
a would be equal to -(1/3)
b would be equal to -(1/3)
c would be equal to 4
If you were given this equation in this form to start with and asked to solve for the roots, you would have done the following:
Multiply both sides of the equation by (-3) to get:
x^2 + x - 12 = 0
Factor this equation to get:
(x-3) * (x+4) = 0
Solve for x to get:
x = 3
or:
x = -4
which is where you started from.
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