Well in order to solve this problem we need to simplify it so lets get to the math part. BELOW xD
The area of a trapezoid is A = 1/2 x height x( a+b) a and b are the lengths of the parallel sides...A=1/2×6x×(3x+5x)
Then simplify it and it will look like this. 24x2 so just multiply it. and get 48.
Hope this helps you in Biology.