Question

How do you solve `x^2+y^2=153, y=-4x`?

Answer 1

`x={-3,+3}`

Explanation:

`x^2+y^2=153`
`y=-4x`

`(y^2)=(-4)^2`
`(y)^2=16x^2`

`x^2+16x^2=153`
`17x^2=153`

`x^2=153/17`

`x^2=9`

`x={-3,+3}`