GMAT Prep 2 Problem- Please help

[jaydeer44]

Can someone please explain how to solve this problem? The answer is E) 20.

Thanks!

[Suyog]

( root (9 + root 80) + ( root (9 - root 80) )^2

= 9 + root 80 + 2((root (9 + root 80) (root (9 - root 80)) + 9 - root 80

= 18 + 2 (root(81-80)).......... ( root( 81 + 9root80 - 9root80 - root 80 * root 80)

= 18 + 2(roor1)

= 20

Choose(e)

[jaydeer44]

thanks! wow, so there is no shorter method of doing this is there? This method takes me so long and there is so much room for error in my calculations! ughhh