SOLUTION: (7x + 9)^2 - 7 = 43

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Question 243570: (7x + 9)^2 - 7 = 43
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

%287x%2B9%29%5E2-7=43 Start with the given equation.


%287x%2B9%29%5E2=43%2B7Add 7 to both sides.


%287x%2B9%29%5E2=50 Combine like terms.


7x%2B9=%22%22%2B-sqrt%2850%29 Take the square root of both sides.


7x%2B9=sqrt%2850%29 or 7x%2B9=-sqrt%2850%29 Break up the "plus/minus" to form two equations.


7x%2B9=5%2Asqrt%282%29 or 7x%2B9=-5%2Asqrt%282%29 Simplify the square root.


7x=-9%2B5%2Asqrt%282%29 or 7x=-9-5%2Asqrt%282%29 Subtract 9 from both sides.


x=%28-9%2B5%2Asqrt%282%29%29%2F7 or x=%28-9-5%2Asqrt%282%29%29%2F7 Divide both sides by 7 to isolate 'x'.


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Answer:


So the solutions are x=%28-9%2B5%2Asqrt%282%29%29%2F7 or x=%28-9-5%2Asqrt%282%29%29%2F7.