Area of a triangle with base b and height h is

• A. b h
• B. 1/2 b h
• C. 2 b h
• D. pi r^2

Answer: (B)

The area of a triangle equals half the product of its base and height. If you imagine a rectangle with the same base and height, its area is base times height. A triangle fits into exactly half of that rectangle, so its area is half of base times height.

For a base b and height h, that gives (1/2) × b × h. The other expressions don’t match a triangle’s area: base times height is the rectangle area, twice that would be too large, and pi r^2 is the area of a circle.