Question

Find the x- and y-intercepts of the graph of the equation y = x2 + 3x – 40.

Answer 1

The quadratic equation given is,

$y=x^2+3x-40$

To find the x-intercept (s), we set y = 0. So,

$\begin{gathered} y=x^2+3x-40 \\ 0=x^2+3x-40 \\ (x+8)(x-5)=0 \\ x=-8,5 \end{gathered}$

To find the y-intercept, we set x = 0. So,

$\begin{gathered} y=x^2+3x-40 \\ y=0^2+3(0)-40 \\ y=-40 \end{gathered}$Answersx-intercepts --- x = - 8, x = 5y-intercept --- y = - 40