Question

What are the x-intercepts of y=2x^2+6x-20?

Answer 1

The x-intercepts would be (2, 0) and (-5, 0).

Explanation:

To find the x-intercepts, substitute in 0 for y and solve for x.

0 = 2x^2 + 6x - 20.

Solve the equation.

x = 2, -5.

Answer 2

the x-intercepts are -5 and 2

Explanation:

`y=2x^2+6x-20`

x-intercept is when y is set equal to zero

So, y = 0

`0 = 2x^2+6x-20`

`2x^3+6x-20 = 0\\Taking \ 2 \ common\\2(x^2+3x-10) = 0\\Dividing \ both \ sides \ by \ 2\\x^2+3x-10 = 0\\Using \ mid\ term \ break \ formula\\x^2+5x-2x-10 = 0\\x(x+5)-2(x+5)=0\\Taking \ (x+5) \ common\\(x+5)(x-2) = 0`

Either,

x+5 = 0 OR x-2 = 0

x = -5 OR x = 2

So, the x-intercepts are -5 and 2