So to find the area of a Triangle you want to use the equation:
A=B*H/2.
So for the base we use 18 and for the Height we use 8.
Then just do the equation. A=18*8/2=72in.
So to find the area of a Trapezoid you want to use the equation:
A=1/2h(b₁+b₂)
So the numbers we will be using is: 7,7,15.
Put the numbers in the equation: A=1/2(7)(7+15).
Then just do the equation. A=1/2(7)(7+15)=77yards