Answer:
Depends on domain of x, could be
-√(y+10)/7; √(y+10)/7 or no solutions
Explanation:
You need to solve it for x:
y=7x^2-10
7x^2=y+10
x^2=(y+10)/7
In order for this equation to have an inverse, you need to check the domain of x. There needs to be only one solution for x^2=(y+10)/7 - either positive or negative, depending on the domain.