Area of triangle ABC?

A normal-level "Area" problem.Either diagonal halves it — parallelogram, rectangle, rhombus or square, it makes no difference.

GivenParallelogram ABCD has area 48 cm²

Hints

1. The diagonal AC splits the parallelogram into two triangles. Compare them.
2. In a parallelogram opposite sides are equal: AB = DC and BC = AD (see the marks).
3. And the diagonal AC is a side shared by both triangles. So all three pairs of sides match: the two triangles are identical in shape and size.
4. Check it: rotate 180° about the midpoint of AC and the red triangle lands exactly on the blue one.
5. Two equal halves make the whole parallelogram, so the answer is 48 ÷ 2.

Answer 24cm²

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