Given:
The parallel sides of a trapezium are 28.7 cm and 22.3 cm.
The distance between parallel sides is 16 cm.
To find:
The area of a trapezium.
Solution:
The area of the trapezium is:

Where,
are parallel sides and
is the vertical distance between the parallel sides.
Putting
in the above formula, we get




Therefore, the area of the trapezium is 408 square cm.
You will have to use trig to solve this:
The side you have is adjacent to the known angle
The side you are looking for is opposite the known angle
^^^This means you need to use tan:
tan(24) = 
.445222 = 
^^^input tan(24) into calculator, then multiply 12 to both sides to isolate and solve for x
5.3 ≈ x
Hope this helped!
Make a proportion
81/30 = x/600
600/30 = 20
x/81 = 20
x = 1620
Solution: 1620 calories