Which equation is the quadratic variation for the relationship? y varies directly with x^2 and y=36 when x=3

a: y = 1/4x^2
b: y=12x
c: y=4x^2
d: y=x^2+25

Type the correct answer in the box. consider the system of linear equations below. rewrite one of the two equations above in the form ax + by = c, where a, b, and c are constants, so that the sum of the new equation and the unchanged equation from the original system results in an equation in one variable.