Question

If x=2y+1 what is th e value of 10y-5x

Answer 1

`x=2y+1`

what is
`10y-5x`?

all you gotta do is substitute the value of
`x` in the equation:

`x=2y+1\\10y-5(2y+1)`

now solve for
`y`:

`10y-5(2y+1)\\10y-10y-5=-5`

so the value of
`10y-5x =`
`\boxed{-5}`