Common Assessment
8th Math Unit #5
Similar Figures & Transformations
1. Brad drew a rectangular sketch in art class
with dimensions 8 inches long by 10 inches
wide. He decided to dilate his sketch so that
the sketch would have a width of 15 inches.
What was the length of the new sketch?
Name:________________________Period:______
3. Josh is 1.8 meters tall. On a sunny day,
Lenny measured Josh’s shadow and the
shadow of their house at the same time. If
the length of the house’s shadow is 5 times
the length of Josh’s shadow, what is the
height of the house?
A. 12
B. 13
C. 17
D. 19
__________________________________________
2. Triangle ABC is shown on the coordinate
plane below.
Record your answer and fill in the bubbles
on your answer document. Be sure to use the
correct place value.
__________________________________________
4. Esmeralda works in the snack bar at the
movie theater. She serves popcorn in the two
sizes shown below.
If a dilation image of Triangle ABC has a
scale factor of 2, which ordered pair would
NOT be a vertex of this dilation?
A. (4, 0)
If the dimensions of the large box are
proportional to the dimensions of the small
box, what is the width, x, of the large box?
B. (0, 4)
C. (-4, -4)
D. (4, -4)
A. 2
2
5
B. 6
2
3
C. 8
D. 10
5. Carl is a photographer. He has taken a
photograph of a very tall statue. The length
of the shadow of this statue was 8 feet.
When he looked at the picture, he saw the
shadow’s length was 3 centimeters and the
height of the statue in this picture was 7
centimeters. What was the actual height, in
feet, of the statue?
7. A small garden was built inside an empty
lot. The two triangles formed are similar.
What is the length of
?
3
A. 3 7 ft.
5
B. 2 8 ft.
C. 15 ft.
D. 18
2
3
ft.
A. 5 ft.
B. 12 ft.
C. 15 ft.
D. 6 ft.
__________________________________________
__________________________________________
6. Triangle ABC is similar to Triangle DEF.
8. Myra’s sailboat has a small glass window
that allows light to enter the cabin. The
window is shaped like a rectangle with
semicircles on both ends and has the
dimensions shown in the diagram below.
What is the value of x?
Which of these measures is closest to the
area of the glass window? (Use π = 3.14)
Record your answer and fill in the bubbles
on your answer document. Be sure to use the
correct place value.
A.
B.
C.
D.
50.24 square inches
53.12 square inches
73.12 square inches
98.24 square inches
9. The graph below shows that Triangle ABC is
a dilation of Triangle DEF.
A. Y' (-3, -8); Z' (2, -3)
B. Y' (2, -6); Z' (-3, -6)
C. Y' (2,-3); Z' (-3,-8)
What is the scale factor used to create
Triangle ABC?
A. 1.0
B. 1.5
C. 2.0
D. 2.5
__________________________________________
10. Which set of ordered pairs represents the
three vertices of Figure A reflected across
the y-axis?
D. Y' (2,-3); Z' (-3, -4)
__________________________________________
12. The local Teen Recreational Center plans to
put new carpet on their game room floor.
The floor is in the shape of a square. If the
perimeter of the floor is 144 feet, how many
square feet of carpet will be needed to cover
the floor?
A.
B.
C.
D.
A.
B.
C.
D.
(4, 2), (6, 2), (5, 5)
(2,2), (7, 2), (-6, 5)
(3, 2), (-6, 2), (5, 5)
(3, 2), (7, 2), (5, 5)
11. Triangle XYZ is translated so that X is mapped
to X'. Which coordinate pairs best represent Y'
and Z'?
1,296 ft.2
48ft.2
72 ft.2
5,184 ft.2