Area of polygons and compound shapes (7th grade geometry)

First, we review (or learn) the formulas for the area of a parallelogram, triangle, and trapezoid. Then we look at a problem with a rhombus divided into four congruent triangles. The area is given and the base of each triangle is given, and we need to find the height of each triangle. An equation works well... but there are other ways to find the answer, too.

The other question has to do with a trapezoid that is enlarged with a scale factor of 1.5. What is its area after the transformation?

See also

Problems Involving Circles

Math Mammoth Geometry 3 — a self-teaching worktext with explanations & exercises (grade 7)

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