First you would need to find the square root of 50. Therefore, when x is t the power of 2, your x value would equal to the square root of 50.
EX: x to the power of 2= 100.... x would equal to 10, since the square root of 100 is 10 and 10to the power of two ( or by itself twice) is equal to 100 it is similar to this equation....
your answer for your equation is 7.07106781187
Hope this helps:)