SOLUTION: Solve the following quadratic equation for the indicated variable. y2 − 3y = 9x for y

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Question 840386: Solve the following quadratic equation for the indicated variable.
y2 − 3y = 9x
for y
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
You would really mean y%5E2-3y=9x if this is supposed to be quadratic.

Completion of Square is needed to solve for y.
Without explaining the choice,
y%5E2-3y%2B%283%2F2%29%5E2=9x%2B%283%2F2%29%5E2
%28y-%283%2F2%29%29%5E2=9x%2B%283%2F2%29%5E2
y-3%2F2=0%2B-+sqrt%289x%2B9%2F4%29
highlight%28y=3%2F2%2B-+3%2Asqrt%28x%2B1%2F4%29%29


This could have also been done using the general solution to a quadratic formula, itself which relies on Completing the Square to obtain the general solution.