Question

What are the x-intercepts of the graph of the equation y = x² + 4x - 5 ?

5 and 1
-5 and 1
-5 and 0
5 and -1

Answer 1

The x-intercepts of the graph of the equation y = x² + 4x - 5 is -5 and 1

Explanation:

Given:

y = x² + 4x-5

To Find:

x-intercepts

Solution:

Finding the value of the x by using quadratic formula

x =
`(-b \pm √(b^2 -4ac))/(2a)`

On substituting the values ,

x =
`(-4 \pm √((4)^2 -(4(1)(-5))))/(2(1))`

x =
`(-4 \pm √(16 -(-20)))/(2)`

x =
`(-4 \pm √(36))/(2)`

x =
`(-4 \pm6 )/(2)`

`x = (-4-6)/(2)`
`x = (-4+6)/(2)`

`x = (-10)/(2)`
`x = (2)/(2)`

x = -5 x = 1