1. Find the value of one unknown in either of the given equations.

2. Substitute this value in the other equation.

Solve using substitution:

1. Find the value of y in the first equation y=2x+8

2. Substitute this value in the second equation and solve for x:

3x+2·(2x+8)=9

3x+4x+16=9

7x=9-16

7x=-7

x=-1

To find the y-coordinate, back-substitute the x-value into y=2x+8:

y=2·(-1)+8

y=-2+8

y=-6

The solution is (-1,-6)