Question

How do you solve x+y=7 and x-y=-3?

Answer 1

`x=2`
`y=5`

Explanation:

Given -
`x+y=7` ----------------(1)
`x-y=-3`----------------(2)

Solve the first equation for `y`
y = 7-x#

Substitute this value in equation(2)

`x-(7-x)=-3`
`x-7+x=-3`
`2x=-3+7`
`2x=4`
`x=4/2=2`

Substitute `x=2` in equation (1)
`2+y=7`
`y=7-2`
`y=5`

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