SOLUTION: what value should be added to each side to complete the square of: x^2+20x=-8

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Question 685206: what value should be added to each side to complete the square of:
x^2+20x=-8
Answer by funmath(2933) About Me  (Show Source):
You can put this solution on YOUR website!
what value should be added to each side to complete the square of:
x^2+20x=-8
When you have a binomial in this form:
x%5E2%2Bbx
There is a formula that tells you what will complete the square: c=%28b%2F2%29%5E2
For us...b=20
c=%2820%2F2%29%5E2
c=10%5E2
highlight%28c=100%29
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x%5E2%2B20x%2B100=-8%2B100
%28x%2B10%29%5E2=98
Some find it easier to visualize the end...guessing what it has to be to make a perfect square...that falls apart for most when fractions and decimals are introduced.
Happy Calculating!!!