Is the following not a function ?

What are the solutions to the equation 4x2+3x=24-x

Evaluate the expression for the given value of the variable 2×(c2-5) for c=4

Select the correct answer from the drop-down menu. subtracting 3xy^2 from 8xy^2 gives the same result as the expression. [tex]3xy ^{2} - 8xy ^{2} [/tex][tex] { - 7xy}^{2} - {2xy}^{2} [/tex][tex] {7xy}^{2} - {2xy}^{2} [/tex]