Since we really only need one of each side and not for im going to divide 42/2 and use 21 for my equation. x+(x-3)=21 2x-3=21 2x=24 (/2) x=12 So this means the length is 12, and the width is 3 less so it’s 9. We can check this by doing: (12*2)+(9*2) 24+18 42
