Question

Which equation is a quadratic equation?

5x + y = -2(x + 5)
y - 9 = (x2 + 1)(5x - 1) + 3
y + 7x = -3x(7 - 2x) + 11
3x3 - y = (3x - 2)(x + 5)

Answer 1

help please :(

Answer 2

you want something that has an x^2 term

Answer 3

okay

Answer 4

and you want this to be the largest term (ie you don't want something with x^3, x^4, etc)

Answer 5

so choice D is out because 3x^3 tells us that we're dealing with a cubic (not a quadratic)

Answer 6

ok

Answer 7

what do you get when you expand out choice B?

Answer 8

uhhhh

Answer 9

y - 9 = (x^2 + 1)(5x - 1) + 3

y - 9 = x^2(5x - 1) + 1(5x-1) + 3

y - 9 = 5x^3 - x^2 + 5x-1 + 3

so what type of equation is this?