Question 52495
Just work one equation at a time, and don't forget to distribute correctly.

{{{4x+2y=8}}} and {{{y=2x+1}}}
{{{4x+2(2x+1)=8}}}
{{{4x+4x+2=8}}}
{{{8x+2=8}}}
{{{x=6/8}}} or {{{x=3/4}}}
Plug that into the other equation to get y:
{{{y=2(3/4)+1}}}
{{{y=10/4}}}
{{{y=2&1/2}}}