Let's do this piecework. There's two 7's being added in the perimeter, so 26- 14= 12. Divide by 2 since it's multiplied by two. We get 6. For the area of the rect. it's 7*6= 42. The right trapezoid has a base of CD, or 14-6 = 8, and a top base of 4. using the formula, we do 8+4 times height/2, which is 12 * 7/2, or 84/2 = 42.
If you don't understand feel free to ask/