Call the width, W
Then the length, L, is 4W + 9.7
And the perimeter is 2(W + L) =
2 (W + 4W + 9.7) = 91.4 simplify
2 (5W + 9.7) = 91.4
10W + 19.4 = 91.4 subtract 19.4 from both sides
10W = 72 divide both sides by 10
W = 7.2 cm
And L = 4(7.2) + 9.7 = 38.5 cm
