Which equation is a quadratic equation?
Answer
y + 3 = 5x + 10
y + 4x2 = (4x - 2)(x + 3)
y - 8x = (x2 + 1)(9x - 7)
y = 2x + 7x(x + 1)

Question

Which equation is a quadratic equation?
Answer
		y + 3 = 5x + 10
		y + 4x2 = (4x - 2)(x + 3)
		y - 8x = (x2 + 1)(9x - 7)
		y = 2x + 7x(x + 1)

anonymous · Answer

thanks

jim_thompson5910 · Answer

it's not #3

anonymous · Answer

?

jim_thompson5910 · Answer

y - 8x = (x^2 + 1)(9x - 7)


y - 8x = 9x^3 - 7x^2 + 9x - 7


which is a cubic (and not a quadratic)

apoorvk · Answer

the equation with degree '2', when written in implicit form.

anonymous · Answer

ohhh... so its #2

jim_thompson5910 · Answer

close, but again no

jim_thompson5910 · Answer

y + 4x^2 = (4x - 2)(x + 3)

y + 4x^2 = 4x^2 + 12x - 2x - 6

y = 4x^2 + 12x - 2x - 6 - 4x^2

y = 10x - 6 ... which is linear

anonymous · Answer

confused...  then it has to be the last one... cause im pretty sure the first one isnt a quadratic

jim_thompson5910 · Answer

you got it, you can either use the process of elimination, or you can do...


y = 2x + 7x(x + 1)

y = 2x + 7x^2 + 7x

y = 7x^2 + 9x

which is definitely a quadratic