1. Splash Screen

2. Lesson Menu Five-Minute Check (over Lesson 4–8) Main Idea and Vocabulary Example 1:Use Shadow Reckoning Example 2:Use Indirect Measurement

3. Main Idea/Vocabulary indirect measurement Solve problems involving similar triangles.

4. Example 1 Use Shadow Reckoning TREES A tree in front of Marcel’s house has a shadow 12 feet long. Marcel’s shadow is 3 feet long. If Marcel is 5.5 feet tall, how tall is the tree?

5. Example 1 Use Shadow Reckoning Answer: The tree is 22 feet tall. tree’s shadowtree’s height Marcel’s shadowMarcel’s height 12 ● 5.5 = 3 ● hFind the cross products. Multiply. Simplify. Divide each side by 3.

6. 1.A 2.B 3.C 4.D Example 1 A.4.5 feet B.5 feet C.5.5 feet D.6 feet Jayson casts a shadow that is 10 feet long. At the same time, a flagpole casts a shadow that is 40 feet long. If the flagpole is 20 feet tall, how tall is Jayson?

7. Example 2 Use Indirect Measurement SURVEYING The two triangles shown in the figure are similar. Find the distance d across the stream.

8. Example 2 Use Indirect Measurement Answer: The distance across the stream is 16 meters. Write a proportion. AB = 48, ED = d, BC = 60, and DC = 20 Multiply. Then divide each side by 60. 48 ● 20 = d ● 60Find the cross products. Simplify.

9. 1.A 2.B 3.C 4.D Example 2 A.6 feet B.6.5 feet C.7 feet D.7.5 feet SURVEYING The two triangles shown in the figure are similar. Find the distance d across the stream.

10. End of the Lesson

11. Resources Five-Minute Check (over Lesson 4–8) Image Bank Math Tools Solving Proportions Dilations Similar Triangles

12. 1.A 2.B 3.C 4.D Five Minute Check 1 (over Lesson 4-8) Find the coordinates of the image of the parallelogram ABCD after a dilation with a scale factor of 2. Parallelogram ABCD has vertices at A(1, 1), B(3, 3), C(6, 3), D(4, 1). A.A′(2, 2), B′(6, 6), C′(12, 6), D′(8, 2) B.A′(1, 2), B′(5, 6), C′(12, 12), D′(8, 2) C.A′(6, 6), B′(2, 2), C′(12, 6), D′(2, 8) D.A′(2, 2), B′(6, 6), C′(6, 12), D′(8, 2)

13. 1.A 2.B 3.C 4.D Five Minute Check 2 (over Lesson 4-8) A. B. C. D.

14. 1.A 2.B 3.C Five Minute Check 3 (over Lesson 4-8) Parallelogram ABCD has vertices at A(1, 1), B(3, 3), C(6, 3), D(4, 1). Identify whether the image of parallelogram ABCD after a dilation with a scale factor of 2 is an enlargement or a reduction. A.enlargement B.reduction C.cannot be determined

15. 1.A 2.B 3.C Five Minute Check 4 (over Lesson 4-8) A.enlargement B.reduction C.cannot be determined

16. 1.A 2.B 3.C 4.D Five Minute Check 5 (over Lesson 4-8) Triangle M is similar to triangle N. What scale factor was used to dilate triangle N to M? A.3 B.2 C. D.

17. End of Custom Shows