Asap and show the steps use the substitution method to solve this system of equations: x+3y=8 4x-y=6

Using substitution:In the first equation, look to solve for x 
{x + 3 y = 8
{4 x - y = 6

Subtract 3 y from both sides:
{x = 8 - 3 y
{4 x - y = 6

Substitute x = 8 - 3 y into the second equation:
{x = 8 - 3 y
{4 (8 - 3 y) - y = 6

4 (8 - 3 y) - y = (32 - 12 y) - y = 32 - 13 y:
{x = 8 - 3 y
{32 - 13 y = 6

In the second equation, look to solve for y:
{x = 8 - 3 y
{32 - 13 y = 6

Subtract 32 from both sides:
{x = 8 - 3 y
{-13 y = -26

Divide both sides by -13:
{x = 8 - 3 y
{y = 2

Substitute y = 2 into the first equation:
    {x = 2 
                  {y = 2

This polygon has 4 sides
180(4-2) = 180(2) = 360 degree
80+90+2x + 3x = 360
170+5x = 360
5x = 190
x= 38
measure of angle t is 2(38)= 76
the answer is c. trust me
hope this !