Question

How do you solve the system of linear equations `2x + y = 5` and `x − 2y = 10`?

Answer 1

`x=4`
`y=-3`

Explanation:

first of all make any variable of the any equation the same so we will here take x and the second equation
`2(x-2y=10)` this will make both the x values same
`2x-4y=20` now change the signs of the second equation
so this will give us `-2x+4y=-20`
now write both the equations simultaneously and solve them
`-2x and +2x` will be cancelled `+y+4y=5y` and `5-20=-15`
so `y=-3` Then after getting the value of y put in equation 1 and
solve it `2x +(-3)=5`
`2x=5+3`
`2x=8`
`x=4`