Which formula represents the area of a triangle?

The formula that accurately represents the area of a triangle is A = 1/2 base x height. This formula reflects the geometric principle that the area of a triangle is half of the area of a rectangle with the same base and height. When calculating the area of a triangle, one takes the base as one side of the triangle and the height as the perpendicular distance from the base to the opposite vertex. By multiplying the base by the height and then dividing by two, you arrive at the correct measurement of the triangle's area.

Other formulas listed do not adhere to the geometric properties of a triangle. For example, base x height simply calculates the area of a rectangle rather than a triangle. The formula base + height does not yield an area measurement at all, and base x height x 2 incorrectly suggests that the area of a triangle is twice what it actually is, misrepresenting the fundamental relationship between triangle dimensions.