Please help me with questions 7

Answer:
50 m
Step-by-step explanation:
The area (A) of a trapezoid is found using the formula
A = [tex]\frac{1}{2}[/tex] h(a + b)
where h is the width and a, b the length of the bases
here a = 50, b = 10 and A = 1500
1500 = [tex]\frac{1}{2}[/tex]h(50 + 10) = [tex]\frac{1}{2}[/tex]h × 60 = 30h
divide both sides by 30
50 = h
The width is 50 m