Teaching Algebra with Manipulatives

Formulas
NAME ______________________________________________ DATE ____________ PERIOD ____
Algebra Activity
(Use with Algebra 1, Lesson 3-1)
1. Estimate the area of each figure below. Write your estimate inside the
figure.
2. Compare the areas of the triangles with the areas of the
parallelograms. Now compare the base and height of each triangle with
the base and height of each parallelogram. What conclusions can you
make?
1 2 3 4
5 6 7 8 9
10 11 12
3. Using the formulas you developed for the area of a parallelogram and a
triangle, find the area of each figure above when the scale of the grid is
a. 1 unit 1 cm;
b. 1 unit x cm.
4. On grid paper, draw a triangle, parallelogram, acute triangle, right
triangle and an obtuse angle with different measures for their bases
and height. Find the area of each figure.
© Glencoe/McGraw-Hill 58 Teaching Algebra with Manipulatives