Answer:
29.32 feet
Step-by-step explanation:
area of a trapezoid = height/2 * (first base + second base)
125.4 = 5.3 / 2 * (18 + second base)
125.4 = 2.65 * (18 + second base)
We want to solve for the second base. To do this, we can start by isolating the (18+second base) by dividing each side by 2.65
47.32 = 18 + second base
subtract 18 from both sides to solve for the second base
29.32 = second base