W=x
L=2x+17
Double everything since we need to lengths and two widths to find the perimeter
2x+17+2x+17+x+x = 76
Combine like terms
6x+34=76
Solve for x
First step is subtract 34 from both sides
6x=42
Next you divide both sides by 6 in order to get x by itself
X=7
Now you plug in 7 into the x’s in length and width
W=7 cm
L=31 cm
THE WIDTH IS 31 CM
Check:
7+7+31+31 = 76 cm
It equals 76 cm just like the problem said so therefore it is right.