Here we have the equation given which is 2(8-2x)+2(4-2x)=18 .
Here x is the width and 18 is the perimeter. We need to find the width that is we have to solve for x .
And to solve for x first we distribute 2 on 8-2x and 2 on 4-2x .
2* 8 +2*(-2x) +2(4)+2(-2x)=18
16-4x+8-4x=18
Now we combine the like terms .
16+8 -4x-4x=18
24 -8x =18
Now we need to move 24 to the right side, and for that we subtract 24 .
24-8x-24 =18-24
-8x =-6
Now we need to get rid of -8 and for that we divide both sides by -8 .
x = 6/8 = 3/4 .