1. T3.1b To Find The Area Of Any Triangle Given Three Sides
T3.1b To Find The Area Of Any Triangle Given Three Sides
Thinking questions:
How is this different from what we did in our last lesson? Geometry relationship?
How many sides does a piece of paper have?
Can you change that number?
Got ID?

2. Active Learning Assignment?
Fun Fact #1: 3 out of 4 people make up 75% of the population!
Fun Fact #2: 5 out of 4 people cannot do math!

3. Why separate into two equations?
LESSON: We will use Hero’s or Heron’s formula to find the area of a triangle. The formula is in two parts. First we find the semiperimeter. a b c *
Then, we will use this: *
Why separate into two equations?

4. TRY: Find the area of a triangle having sides of lengths 29 in., 38 in., and 42 in (one decimal place.)
s = 54.5
Then, we will use this:
The area is in2.

5. TRY: The AAA sorority from Bayou Blanc University wants to make the world’s largest pennant. It will measure 300 ft. by 500 ft. by 500 ft. One bolt of material has 750 square feet in it and must be sold as a whole bolt. What is the minimum number of bolts needed? How many would you suggest that they buy?
s = 650
K = 71,545 ft2.
= 95.4 bolts
They will need at least 96 bolts.
Your suggestion?

6. Active Learning Assignment: H/O on Area with 3 Sides (Answers):
#39 (12,609 cm2)
#41 ( ft2)
#43 (1921 ft2)
#45 ( 33)
WOW:
Practice empathy: Try to see things from other people’s point of view.