SOLUTION: find the value of c that makes each trinomial a perfect square: x^2-21x+c.

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Question 595092: find the value of c that makes each trinomial a perfect square: x^2-21x+c.
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
find the value of c that makes each trinomial a perfect square: x^2-21x+c.
:
Divide the coefficient of x by 2, and square it
-21/2 = -10.5; -10.5^2 = +110.25 = c
:
x^2 - 21x + 110.25