Answer :
It depends on whether or not you have written the question correctly. If the 2 is an exponent, it needs to be preceded by a ^. Otherwise, it is considered a multiplier.
x^2 = x²
x2 = x⋅2
y = x²-1 is nonlinear and nonproportional.
x^2 = x²
x2 = x⋅2
y = x²-1 is nonlinear and nonproportional.