1.10 Perimeter and Area
Triangles and Parallelograms
Pacing:This lesson should take one class period
Goal:This lesson introduces students to the area formulas for parallelograms and rectangles. It also illustrates the
relationships between these formulas.
Flashcards!Creating another set of flashcards will be second-nature to our students by now. These flashcards should
also be double-sided. The blank side should be a sketch of the figure and its special name. The flip side should repeat
its definition, the sum of its interior angles, the expression for its perimeter, the formula for its area, and the formula
for its perimeter. Have students create flashcards as the chapter presents the figures; this lesson only covers triangles,
rectangles, and parallelograms.
Visualization!Encourage students to see how a parallelogram can be transformed into a rectangle by performing the
activity presented in the lesson.
Extra Credit?You may want to offer extra credit for students who can correctly determine the total area of the eight
circles found in the introduction of this lesson. 16− 8 ∗(π∗(^12 )^2 ) = 16 − 4 πft^2.
Extension!Using the hexagon below, find its area.Students use the concept of triangles and interior angles.Note**
This may be more appropriate for students to attempt once the trapezoid area formula has been presented.
Trapezoids, Rhombi, and Kites
Pacing:This lesson should take one class period
Goal:This lesson further expands upon area formulas to include trapezoids, rhombi, and kites.
1.10. Perimeter and Area