SOLUTION: Square root of x+56=x

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Question 84334This question is from textbook Prentice Hall Algebra 1 California Edition
: Square root of x+56=x This question is from textbook Prentice Hall Algebra 1 California Edition

Answer by ptaylor(2198) About Me  (Show Source):
You can put this solution on YOUR website!
Square root of x+56=x
sqrt%28x%2B56%29=x square both sides to get rid of the radical and we get:
x%2B56=x%5E2 subtract x and also 56 from both sides
x%5E2-x-56=x-x%2B56-56 collect like terms
x%5E2-x-56=0 quadratic in standard form and it can be factored
%28x-8%29%28x%2B7%29=0
x-8=0
x=8 and
x%2B7=0
x=-7
CK
sqrt%288%2B56%29=8
sqrt%2864%29=8
8=8
sqrt%28-7%2B56%29=-7
sqrt+%2849%29=-7
Since the square root of 49 is plus or minus 7, this solution works also.
(Note: If the A coefficient of a quadratic is 1, then the B coefficient is the sum of the factors of the C coefficient. In this case, the factors of the C coefficient that work are -8 and +7)

Hope this helps---ptaylor