A rectangular trapezoid is given, the smaller base of which is 8 cm. The smaller lateral side is 4 cm, and the larger

A rectangular trapezoid is given, the smaller base of which is 8 cm. The smaller lateral side is 4 cm, and the larger lateral side forms ∡45 ° with the base. Find the area of the trapezoid.

In the constructed trapezoid, we draw the height, which forms an isosceles triangle. The height is equal to the smaller side = 4 cm, the bottom base of the triangle = height = 4 cm, then the whole bottom base = 8 + 4 cm = 12 cm.
S = ((a + b): 2) h = ((8 + 12): 2) * 4 = 40 cm ^ 2
Answer: 40 cm ^ 2