SOLUTION: Let f(x)=13x^2+65x+3. Find a such that f(a)=3

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Question 19850: Let f(x)=13x^2+65x+3. Find a such that f(a)=3
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Did you really mean..."Find x such that f(x) = 3" ??
If f%28x%29+=+13x%5E2%2B65x%2B3, then:
f%28x%29+=+3 = 13x%5E2+%2B+65x+%2B+3+=+3 Solve for x.
13x%5E2+%2B+65x+%2B+3+=+3 Subtract 3 from both sides of the equation.
13x%5E2+%2B+65x+=+0 Factor 13x from the left side.
13x%28x+%2B+5%29+=+0 Apply the zero products principle.
13x+=+0 and/or x+%2B+5+=+0
If 13x+=+0 then, x = 0
If x+%2B+5+=+0 then, x+=+-5
Check:
f%280%29+=+13%280%29%5E2+%2B+65%280%29+%2B+3 = 3
f%28-5%29+=+13%28-5%29%5E2+%2B+65%28-5%29+%2B+3 = 325+%2B+%28-325%29+%2B+3+=+3