SOLUTION: {{{((sqrt(7x-9))^(1/3))+(11)}}}=14

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Question 95257: %28%28sqrt%287x-9%29%29%5E%281%2F3%29%29%2B%2811%29=14
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
%28%28sqrt%287x-9%29%29%5E%281%2F3%29%29%2B%2811%29 = 14
:
Subtract 11 from both sides:
%28%28sqrt%287x-9%29%29%5E%281%2F3%29%29%29 = 14 - 11
:
%28%28sqrt%287x-9%29%29%5E%281%2F3%29%29%29 = 3
:
Cube both sides:
%28%28sqrt%287x-9%29%29%5E%281%2F3%29%29%5E3%29 = 3%5E3
:
That gives us;
sqr%287x-9%29 = 27
:
Square both sides and you have:
7x - 9 = 729
7x = 729 + 9
7x = 738
x = 738/7, a rather nasty fraction, but that is the solution
:
:
Check our solution:
Substitute for x in sqrt%287%28738%2F7%29+-+9%29
sqrt%28738+-+9%29 = sqrt%28729%29 = 27
Cube rt of 27 = 3, so we have 3 + 11 = 14