Since the medium-size triangle has area one square unit and each of the small triangles has area one-half square unit, the medium-size square has area two square units:
Since the parallelogram has area one square unit and each of the small triangles has area one-half square unit, the medium-size rectangle has area two square units:
Since the medium-size triangle (or the parallelogram) has area one square unit and each of the small triangles has area one-half square unit, the large triangle has area two square units:
The small square, the medium-size triangle, and the parallelogram each have area one square unit. These together with the two small triangles (each of which has area one-half square unit) make a square with area four square units:
Since each of the two large triangles has area two square units, half the large square has area four square units; therefore the large square has area eight square units:
The parallelogram (or the medium-size triangle) has area one square unit. This together with a small triangle (which has area one-half square unit) makes a trapezoid with area one-and-a-half square units:
The large triangle has area two square units. This together with the medium-size triangle (or two small triangles) makes a trapezoid with area three square units:
The large triangle has area two square units and the small triangle has area one-half square unit, so the pentagon (or any congruent pentagon) has area two-and-a-half square units:
The medium-size triangle and the parallelogram each have area one square unit and the two small triangles each have area one-half square unit, so the pentagon has area three square units:
More Tangram Activities
(answer sheet) 
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