SOLUTION: please help to solve 3x = 18 - x^2

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Question 64381This question is from textbook An Incremental Development
: please help to solve
3x = 18 - x^2
 This question is from textbook An Incremental Development

Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
First, get your equation into the standard form for quadratic equations: ax%5E2+%2B+bx+%2B+c+=+0
3x+=+18-x%5E2 Add x%5E2 to both sides of the equation.
x%5E2+%2B+3x+=+18 Now subtract 18 from both sides.
x%5E2+%2B+3x+-+18+=+0 Factor this quadratic equation.
%28x+%2B+6%29%28x+-+3%29+=+0 Apply the zero product principle.
%28x%2B6%29+=+0 and/or %28x-3%29+=+0
If %28x%2B6%29+=+0 then x+=+-6
If %28x+-+3%29+=+0 then x+=+3
The solutions:
x+=+-6
x+=+3