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

Question

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

.sam. · Answer

expand all and see whether which one has the highest degree of x^2

anonymous · Answer

isnt there a simpler way to see if the equation is quadratic?

.sam. · Answer

yes

.sam. · Answer

you realize that in y = 2x + 7x(x + 1) , you expand it you'll get x^2

anonymous · Answer

yea

.sam. · Answer

others like 	
y - 8x = (x^2 + 1)(9x - 7)
y + 3 = 5x + 10
y + 4x^2 = (4x - 2)(x + 3)
will give you x^3 or x^4 so that's incorrect

.sam. · Answer

you want quadratic, so,  y = 2x + 7x(x + 1)  expanded you'll get a quadratic

anonymous · Answer

k thanks