Question

Substitute the expression for y into x-2y=1 and solve the equation for x.

X=​

Answer 1

make your question clear

Answer 2

I'm not sure to help you but I can help you out a bit.

Since x - 2y = 1,

x = 1+ 2y

This is expressing x in terms of y.

In addition,

2y = x - 1

y = (x-1)/2

This is expressing y in terms of x.