Question 13698
Area of a trapezoid with base 6 and another base 10 and height 4 is 4*(6+10)/2 = 32 
That's the quick answer...now for how to get it given the instructions above.

imagine a trapezoid with one base (top) of 6 m and the other base (bottom) of 10 m and a height of 4 m. (The height line divides the trapezoid into a right triangle with base and height of 4 m each and a rectangle that is 6 m wide by 4 m high.)

Area of a triangle with base 4 and height 4 is 4*4/2 = 8
Area of a rectangle with sides 4, 6 is 4*6 = 24
Add those and you get 32 sq m