SOLUTION: How do you solve 121x^2-49=0

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Question 296873: How do you solve 121x^2-49=0
Found 3 solutions by richwmiller, stanbon, JBarnum:
Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
think of it as (11x)^2-7^2=0

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
How do you solve
121x^2-49=0
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Factor:
(11x-7)(11x+7) = 0
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11x-7 = 0 or 11x+7 = 0
x = 7/11 or x = -7/11
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Cheers,
Stan H.
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Answer by JBarnum(2146) About Me  (Show Source):
You can put this solution on YOUR website!
121=11%5E2
49=7%5E2
the middle sign is negative so this is a true square
%2811x-7%29%2811x%2B7%29 so this is an easy factor, now set both to 0 and solve for x
11x-7=0
11x=7
x=7%2F11
_____________
11x%2B7=0
11x=-7
x=-7%2F11