# solve for x

• Feb 18th 2011, 05:45 PM
rbursell
solve for x
Can you show me how to solve:

x/4^.5 * x/2^.5 = 50 i know the answer is 141 but need help to get there. Thanks
• Feb 18th 2011, 05:59 PM
kumquat
ok here we need to make sense of the left hand side

(x/4)^0.5 means the square root of that, so we have (x^0.5)/(4^0.5) which equals (x^0.5)/2, if you do the same on the other one you have (x^0.5)/2^0.5.

sqaure both side to remove the sqaure roots and then you get (x/4) x (x/2) = 2500 ----> x^2 = 20,000 -----> x = 100 x 2^0.5 which approximates to 141
• Feb 18th 2011, 06:45 PM
reneebu
ok i get (x/4) x (x/2) = 2500 ----> but you lost me here...where does x^2 = 20,000 -----> x = 100 x 2^0.5 come from ???

I feel like multiplying both sides by 1/4 & 1/2 then take the sqrt of x but it doesn't work.
• Feb 18th 2011, 06:55 PM
reneebu
Quote:

Originally Posted by reneebu
ok i get (x/4) x (x/2) = 2500 ----> but you lost me here...where does x^2 = 20,000 -----> x = 100 x 2^0.5 come from ???

I feel like multiplying both sides by 1/4 & 1/2 then take the sqrt of x but it doesn't work.

now i feel dumb...its Multiply each side by 8 then sqrt...ouch