Let x = width
2x + 3 = length
Area of rectangle is length times width
x(2x + 3) = 77
2x² + 3x = 77
2x² + 3x - 77 = 0
2x² + 14x - 11x - 77 = 0
2x(x + 7) - 11(x + 7) = 0
(2x - 11)(x + 7) = 0
x = 11/2, - 7
Distance/measurements can't be negative so x = 11/2
The length:
2(11/2) + 3
11 + 3
14
Your width is 11/2 feet and your length is 14 feet.