1. Trapezoid: Since the perimeter is 32 and the trapezoid is isosceles, each of the other sides is (1/2)(32 - 14 - 8) = (1/2)(10) = 5. Hint: Draw altitudes from the base of length 8 to the base of length 14. What length does the base of the right triangle have?
2. Triangle inside square: The triangle has a base of 20 and a height of 20. What is the formula for the area of a triangle?
3. The area of the floor is 12 x 16 = 192, and the area of each tile is 2 x 2 = 4. How many tiles do you need to cover the floor, in terms of both of these areas?
You are wrong on both of the other problems. Remember that the area varies as the square of the side length.