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Number Talk. The scale on a map is 6cm : 2kn. If the distance between two cities is 8kn, how far apart in cm are the two cities on the map?. In Chemistry Class there is a girl to boy ratio of 5 : 8. If there are a total of 39 students, how many boys are there?.
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Number Talk The scale on a map is 6cm : 2kn. If the distance between two cities is 8kn, how far apart in cm are the two cities on the map? • In Chemistry Class there is a girl to boy ratio of 5 : 8. If there are a total of 39 students, how many boys are there? In Geometry Class, the girl to boy ratio is 8 to 6. If there are a total of 42 students, how many girls are there?
Postulate 25 • Angle-Angle (AA) Similarity Postulate If two angles of one triangle are congruent to two angles of another triangle, then the two triangles are similar.
Similar Triangles • Given the triangles are similar. Find the value of the variable. )) m )) ) 6 8 11m = 48 ) 11
Warm Up: Determine whether the triangles are similar. 6 32° 33° 9 18 No, because two angles of one triangle are not congruent to two angles of another triangle.
Determine whether the triangles are similar. 60° 60° 60° 60° Yes, because two angles of one triangle are congruent to two angles of another triangle.
Given two triangles are similar, solve for the variables. 2b - 8 a + 3 14 15 16 ) ) 10 15(a+3) = 10(16) 15a + 45 = 160 15a = 115
Decide whether two triangles are similar, not similar, or cannot be determined. A 92° 31° S 47° 41° 92° 57° S + 92 + 41 = 180 S + 133 = 180 S = 47 A + 92 + 57 = 180 A + 149 = 180 A = 31 Not similar
Good Afternoon – Agenda • Number Talk • Discuss Overlapping Triangles • Warm Up • Partners • Begin assignment (will finish tomorrow)
Number Talk • A child can run 4 blocks in 2 minutes. How long does it take the child to run 12 blocks? A child can run at a rate of 2 1/2 blocks per minutes. How long does it take the child to run 7 blocks?
Similar Triangles • Given the triangles are similar. Find the value of the variable. Left side of sm Δ Base of sm Δ Left side of lg Δ Base of lg Δ = 6 5 > 2 6h = 40 > h
∆ABC is similar to ∆DBE. A 5 D y 9 x B C E 8 4
2 Practice Problems • For each problem. Show your solutions mathematically as well as explain what you did in plain English. • For Example • “When setting up the proportion 4/x = 15/5 I knew that EB corresponds with DC and EA corresponds with AD.”
Number Talk • What is 40 divided by 1/2, plus 15?
Number Talk • Jasmine has a toaster with two slots that toasts one side of each piece of bread at a time, and it takes one minute to do so. If she wants to make 3 pieces of toast, what is the least amount of time she needs to toast them on both sides?
Quiz Time • 6th Period : 3711870509 • 7th Period: 9841870510