If 4x = 9y, and 2x + 5y = 95. What is the value of y^2 - x?

This is a simultaneous equation problem.If 4x = 9y then 2x = 4.5y.Then by substitution, 4.5y + 5y = 95.Then 9.5y = 95 (divide by 9.5) gives y = 10.By using back substitution 2x = 4.5*10 = 45 (divide by 2 to give x)x = 22.5.Once we have y and x, y^2 - x is numerical. 10 ^2 = 100 x = 22.5y^2 - x = 100 - 22.5 = 77.5Answer: 77.5