Question

Question #29fca

Answer 1

`x=3 and y=-1`

Explanation:

First, as there are 2 unknowns in the question, we can find the relationship bewteen the 2 unknowns, like `x= ?`

In this question,
`x-y=4` .......... `(1)`
`x^2-y^2=8` ..........`(2)`

From `(1)`, we know that `x=4+y`.........`(3)`
Then, we can sub `(3)` into `(2)`,
`(4+y)^2-y^2 =8`
`4^2+2*4*y+y^2-y^2=8`
`16 +8y=8`
`8y=-8`
`y=-1`

We get the value of `y`, but we still don't know `x`, so we can sub `y=-1` into `(3)`
`x=4+y=4+(-1)=4-1=3`

Here we get `x=3 and y=-1` and it's the answer. Hope this can help you :)