1. 7.4 Areas of Triangles and Quadrilaterals
Learning Objective: To find the areas of triangles and quadrilaterals and use the formulas in real world applications
Warm-up (IN)
1. Find the side length of an equilateral triangle with perimeter 15.
2. Find the side length of a square with perimeter 36.
3. Find the lengths of the legs of an isosceles triangle with base 12 and perimeter 28.
4. Find the lengths of the other sides of a parallelogram with one side 4 and perimeter 40.
5. Find the height of an equilateral triangle whose sides are 5 units long. 5 9
15 Minutes - The first part of the warm-up will be a review of the last lesson, and the 2nd is an algebra review to prepare the students for the algebra that will be done in the notes and homework with isosceles triangles.
20 minutes – Check answers to even problems from HW, then to over any questions. 8
4, 16, 16
About 4.3 units

2. Notes Area Formulas Rectangle Square Triangle h h b s b Parallelogram
Learning Objective: To find the areas of triangles and quadrilaterals and use the formulas in real world applications
Notes
Area Formulas
Rectangle
Square
Triangle b h s b h
Parallelogram
Trapezoid
41 minutes for notes
Essential Questions:
What is the isosceles triangle theorem and it’s converse? h b h

3. Learning Objective: To find the areas of triangles and quadrilaterals and use the formulas in real world applications
EX 1 – Find the area of an isosceles trapezoid with perimeter 48 in. if the lengths of the bases are 14 in. and 18in. 2 2
Essential Questions:
How can you use the Isosceles triangle theorem to write a paragraph proof?

4. EX 2 – Find the area of the parallelogram 5 ft
Learning Objective: To find the areas of triangles and quadrilaterals and use the formulas in real world applications
EX 2 – Find the area of the parallelogram
5 ft
13 ft
Essential Questions:
What are the median and altitude of a triangle?

5. 8 minutes for CKC
The students will do the Checking Key Concepts on separate paper to trade and grade.

6. Out – The sides of 2 parallelograms are congruent
Out – The sides of 2 parallelograms are congruent. Must their areas be the same? Explain.
Summary – Today, I learned…
HW – p. 364 #1-7, 10-13, odd
5 minutes for Summary and closing questions.
I will have the students do the Out as a ticket out.