Answer:
See below 
Explanation:
Here is how to start....you didn't include the equations in question, so I do not know what the answer may be
solve for x
y-10 = 5 x^2 divide thru by 5 
(y-10)/5 = x^2 'sqrt' both sides 
± sqrt( (y-10) / 5 = x change x's and y's 
± sqrt ((x-10)/5) = y