Question

Which equation is a quadratic equation?

A. 5x − 2 = y
B. y + 15x2 = (3x − 2)(5x + 7)
C. y = 3x(5 − x) + 7
D. y + 2 = (3x2 + 10)(x − 1)

Answer 1

quadratics have only 2 xs floating around in them

Answer 2

well, at most one set of variable is doubled floating about

Answer 3

A: x
B: xx=xx but they cancel
C: xx
D: xxx