1. DRILL: Solving a proportion
MODEL BUILDING. A scale model of the Titanic is inches long and inches wide. The Titanic itself was feet long. How wide was it?
Width of Titanic
Length of Titanic =
Width of model
Length of model
LABELS:
Width of Titanic = x
Width of model ship = in
Length of Titanic = feet
Length of model ship = in.

2. Solution Write the proportion. Substitute.
Multiply each side by
Use a calculator.
Width of Titanic
Length of Titanic =
Width of model
Length of model
x feet
feet =
11.25 in.
107.5 in.
11.25(882.75) x =
107.5 in.
x ≈ 92.4 feet
So, the Titanic was about 92.4 feet wide.

3. DRILL (Part 2)
You are the architect for a company who is going to build the LUXOR Hotel and Casino (3rd Largest in the world) in Las Vegas, you want to build a smaller scale model of the Hotel prior to building the real one If the actual height of the pyramid is 350 feet, what would be the height of the scale model using a scale factor of 1/70?
350/70 = 5 feet

4. Similarity in Right Triangles
OBJECTIVE: SWBAT Set up proportions in right triangles in order to solve real world problems.
Chapter 10 Section 3
Similarity in Right Triangles

5. Theorem 10.3
The altitude of the hypotenuse of a right triangle divides the triangle into two triangles that are similar to the original triangle and each other.
Triangles ABC, ADB and BDC are all similar triangles, since BD is the altitude to the hypotenuse of triangle ABC. B A C D

6. Geometric Mean
The geometric mean of two numbers (a & b) is the value of “x” when a/x = x/b.
The length of BD is the geometric mean of the two segments of the hypotenuse AC. B A C D

7. Homework Page 507 #’s 1 – 6, 13, 15, 16, 18, 20 – 23 Page 514
DUE on Wednesday!