2.5 Proportions
2.6A Similar Figures
2.6B Shadow Problems
2.7A Dilations
2.7B Scale Factor
100
Are 3/5 and 18/25 proportional?
No. 1) cross products aren't equal or 2) you cannot multiply 3/5 by an equivalent form of 1 to get 18/25
100
Are the triangles similar?
Yes, sides are proportional. Therefore, the triangles are similar.
100
A giraffe is 18 ft tall and casts a shadow of 12 ft. Corry casts a shadow that is 4 ft long. How tall is Corry?
6 ft tall
100
If k=4, what are the coordinates of Q'?
Q(-2,2) therefore Q'(-8,8)
100
Determine the scale factor from Rectangle A to B.
k=1/2
200
Solve.
6/10=x/20
x=12
200
Find x.
x=9
200
A lamppost that is 3 m tall casts a shadow that is 4 m long. At the same time, a nearby tree casts a shadow that is 10 m long. How tall is the tree?
7.5 m
200
What are the coordinates of Q', if triangle QRS is dilated by a scale factor or 3?
Q(-1,-2) so Q'(-3,-6)
200
Determine the scale factor.
k=1/3
300
Solve.
(x-1)/21=3/7
300
Are the triangles similar?
No. The sides are not proportional.
300
A flagpole casts a shadow that is 28 ft long. A 6 ft tall person standing nearby casts a shadow that is 8 ft long. How tall is the flagpole?
21 ft
300
If the scale factor is 1/3 , what are the coordinates of C'?
C(-3,6) therefore C'(-1, 2)
300
Determine the scale factor.
k=4