Do Now 2/24/10 Take out HW from last night. Text p. 295, #6-9 all, & 12 Text p. 295, #6-9 all, & 12 Copy HW in your planner. Text p. 295, #10-15 all Text p. 295, #10-15 all Quiz sections 6.4 & 6.5 Monday Quiz sections 6.4 & 6.5 Monday Review “Geometry NJASK7 Prep” assignment on MySkillsTutor – Quiz Friday Review “Geometry NJASK7 Prep” assignment on MySkillsTutor – Quiz Friday
Homework Text p. 295, #6-9 all, & 12 6) 24 inches 7) 15 mm 8) 9 cm 9) 12.5 yd 12) a. 63 in. b ft. or 15 ft. 9 in.
Objective SWBAT find unknown side lengths of similar figures using indirect measurements
Section 6.4 “Similar and Congruent Figures” Similar Figures Two figures are SIMILAR FIGURES if they have the same shape but not necessarily the same size. The symbol ~ indicates two figures are similar. Properties of similar figures: 1). Corresponding angles are congruent 2). Corresponding sides are proportional (equal ratios)
Section 6.5 “Similarity and Measurement” Given ABCD ~ GHIJ, find HJ. G H IJ AB CD x 16 Cross multiply
C A B a Z Y X z Given ABC ~ XYZ, find a and z.
Indirect Measurements You measure the shadow of a telephone pole to be 30 ft. The shadow of a 6ft-tree is 4 ft. How tall is the telephone pole? S H s h
Indirect Measurements To estimate the height of the Transco Tower in Houston, TX, you measure its shadow to be about 55m. The shadow of a 50m flagpole is about 10m. Estimate the height of the Transco Tower. S H s h
Using Algebra and Similar Triangles B A EC D Given ABC ~ DEC, find BE. x Cross multiply
Find the length of BF given that ABCD ~ CEFG. BFC AD EG 8 cm 9 cm 18 cm 18 cm x Using Algebra and Similar Figures
Homework NJASK7 Prep Text p. 296, #10-15 all