SOLUTION: Find the value of c that will make; 9x2+30x+c a perfect square trinomial thank -you please help

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Question 118283: Find the value of c that will make;
9x2+30x+c a perfect square trinomial
thank -you please help

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Find the value of c that will make;
9x2+30x+c a perfect square trinomial
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Form:
(a+b)^2 = a^2+2ab+b^2
Your Problem:
a^2 = 9x^2 implies that a = 3x
2ab=30x implies that 2(3x)b = 30x implies that b = 5
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Therefore 9x^2+30x+25 is a perfect trinomial square.
Therefore c = 25
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Cheers,
Stan H.