There is a trapezoid with a base angle of 45 degrees, an upper base of 8 cm and a lower base of 12 cm. What is the area of this trapezoid?

There is a trapezoid with a base angle of 45 degrees, an upper base of 8 cm and a lower base of 12 cm. What is the area of this trapezoid?

﹙8＋12﹚×2÷2=20㎝²

An isosceles trapezoid, the base angle is 45 degrees, the upper bottom is 8 cm long, the lower bottom is 14 cm long. How many square centimeters is the area of this isosceles trapezoid?
Please explain why you want to do this

The height of this isosceles trapezoid = (14-8) / 2 = 3
Area = (8 + 14) * 3 / 2 = 33 cm 2
Here the key requirement is high
Because the base angle is 45 degrees, the height = (14-8) / 2 = 3, as shown in the figure:

An isosceles trapezoid with a base angle of 45 ° is 8 cm long at the top and 12 cm long at the bottom. What is the area of this trapezoid?
What is the area of △ BOC if the area of trapezoidal ABCD is 45 square centimeters, the length of its bottom is 9 centimeters, the height is 6 centimeters, and the area of △ AOD is 7.2 centimeters?

The first question is 20. The second question is 16.2