Area of a Triangle

Today we find the area of any triangle using one simple formula. The area of a triangle is half the base times the height.

Let me draw a triangle with a base and height marked clearly. The base is one side of the triangle, say the bottom one. The height is the perpendicular distance from that base to the opposite vertex.

• base = one side
• height = perpendicular to base

Let's use a concrete example: base equals six and height equals four. Plug into the formula: A equals one half times six times four.

• Example: b = 6, h = 4

That simplifies to one half times twenty-four, which is twelve square units.

Why half? Because a triangle is exactly half of a rectangle with the same base and height. This formula works for any triangle: acute, right, or obtuse. Quick check: if base is ten and height is three, what is the area?

• Triangle = half rectangle
• Works for all triangle types

The area of a triangle is always half base times height, no matter its shape.