Here's the question you clicked on:
2016740e
Which equation is a quadratic equation? Answer 5x + y = -2(x + 5) 3x3 - y = (3x - 2)(x + 5) y + 7x = -3x(7 - 2x) + 11 y - 9 = (x2 + 1)(5x - 1) + 3
the last one is because it has an x^2 and if it has x^2 then you know its quadratic