SOLUTION: write the quadratic equation whose roots are 3 and -4 and whose leading coefficient is 4.

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Question 764755: write the quadratic equation whose roots are 3 and -4 and whose leading coefficient is 4.
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!
the quadratic equation is y=ax%5E2%2Bbx%2Bc
if leading coefficient is 4, we have a=-4; so, the quadratic equation is y=4x%5E2%2Bbx%2Bc
if roots are x%5B1%5D=3 and x%5B2%5D=-4, we can use zero product rule to find equation:
y=%28x-x%5B1%5D%29%28x-x%5B2%5D%29...plug in given values for roots
y=%28x-3%29%28x-%28-4%29%29....multiply
y=x%5E2%2B4x-3x-12.......now multiply each coefficient by 4 since given that leading coefficient is 4
y=4x%5E2%2B4x-48
check it on a graph:
+graph%28+600%2C+600%2C+-10%2C+10%2C+-50%2C+10%2C4x%5E2%2B4x-48%29+