SOLUTION: Find the value of c such that z^2 + 10z + c is a perfect square.

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Question 84870: Find the value of c such that z^2 + 10z + c is a perfect square.
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
To find c, simply take half of 10 and square it like this:

c=%2810%2F2%29%5E2

c=5%5E2=25

So c=25. Notice if we have

z%5E2+%2B+10z+%2B+25 it factors to

%28z%2B5%29%5E2 which shows it's a perfect square.