Name: ________________________________
Class: _______________
Date: ___________
Perimeter and Area of Similar Figures
Find the perimeter and area of each set of figures below. Leave all answers as EXACT.
1. Square
A’
A
B’
B
8in
2in
D
C
2. Rectangle
A
D’
9m
C’
B
3m
A’
3m
B’
1m
D’
D
C’
C
3. Triangle
A’
A
25ft
20ft
5ft
4ft
C
B
B’
C’
4. Parallelogram
52cm
B’
13cm
B
A
5. Trapezoid
B
C
4cm
16cm
A’
D 3cm
30yd
D’ 12cm
C
B’ 10yd C’
39yd
39yd
13yd
A
60yd
C’
D
A’
13yd
20yd
D’
6. Rhombus
B’
85mm
B
17mm
16mm C
A
A’
80mm
C’
D
D’
7. Circle
C
36in
Shape
C’
6in
Scale
Perimeter
Scale
Perimeter
Factor of of Original
Factor of
of Image
Dimensions
Figure
Perimeters
Area of
Original
Figure
Area of
Image
Square
Rectangle
Triangle
Parallelogram
Trapezoid
Rhombus
Circle
What do you notice about the scale factor of the perimeters compared to the scale factor of the
dimensions?
How does the scale factor of the dimensions relate to the scale factor of the areas?
Scale
Factor
of Areas
Dimensional Change Worksheet
1) A square has a perimeter of 28. If the sides are all doubled in length, what is the new perimeter?
2) A rectangle with perimeter of 32 feet has all its sides cut in half. IF the original area was 6o square feet,
what is the area of the new smaller rectangle?
3) A rectangle has an area of 135 square inches. It is reduced to an area of 15 square inches. What is the
scale factor for the sides?
4) A square has an area of 256 square inches. If the sides are dilated by a scale factor of 4, what is the scale
factor between the old and new areas?
5. A regular heptagon has a perimeter of 24 ft. It is dilated so that its new perimeter is 96 ft. If the original
heptagon had an area of 30 ft2, what would be the area of the new heptagon?
6. A regular polygon with area 99 square cm is reduced by a scale factor of 1/3 on all sides. What is the area
of the new polygon?