Area of a parallelogram with base b and height h equals

• A. b + h
• B. 2 b h
• C. bh
• D. pi r^2

Answer: (C)

The area of a parallelogram is found by multiplying its base by its height, where height is the perpendicular distance between the bases. This works because you can think of cutting or sliding the shape to turn it into a rectangle with the same base and height; the rectangle’s area is base times height, so the parallelogram shares that same area. With base length b and height length h, the area is bh.

Adding base and height doesn't measure area, and a circle's area is given by pi r^2, which is not relevant here. Doubling bh would overcount the true area. So bh is the correct expression.