Posted by Knights on Wednesday, December 19, 2012 at 12:29pm.
Hi I do not how to simplify the problem
x^2 =40+12sqrt2
what would be x? BTW if you sqrt both sides it would be double square root so what then? how to simplify?

double square root problem?  Damon, Wednesday, December 19, 2012 at 2:30pm
12 sqrt 2 = x^2  40
144 (2) = x^4 80 x^2 + 1600
x^4  80 x^2 + 1312 = 0
graph to find zeros
http://mathportal.org/calculators/polynomialssolvers/polynomialgraphingcalculator.php
zeros at
x = 7.55, 4.80 + 4.80, +7.55
check those in original
+ and  7.55 works
the 4.8 does not