Question

How do you solve by substitution `4x + 6y = 62` and `10x - 2y = 2`?

Answer 1

`10x-2y=2`
`10x=2+2y` ( we add `2y` on each side )
`10x-2=2y` ( we substract `2` on each side )
`5x-1=y` ( we divide by `2` on each side )

Now that we have `y`, we can use substitution in the first equation :

`4x+6*(5x-1)=62`
`4x+30x-6=62`
`34x-6=62`
`34x=62+6` ( we add `6` on each side )
`34x=68`
`x=68/34=2` ( we divide by `34` on each side )

Now that we have `x`, we can find `y` :

We know that `y=5x-1`, as we calculated it before :

`y=5*2-1=10-1=9`