Name:
Math 128 Exam I
Tuesday, February 16, 2010
Problem
Number
1
2
3
4
5
6
7
8
Total
Possible Score
Points
5
9
6
6
6
6
6
6
50
Directions—Please Read Carefully! You have 75 minutes to take this exam. Make
sure to use correct mathematical notation. To receive full credit on a problem, you will need
to justify your answers carefully unless indicated otherwise—unsubstantiated answers will
receive little or no credit. Please be sure to write neatly—illegible answers will receive little
or no credit. If more space is needed, use the back of the previous page to continue your
work. Be sure to make a note of this on the problem page so that the grader knows where
to find your answers.
Calculators are allowed.
Good Luck!!!
1. (5 points) Determine whether each of the following statements are true or false. Circle
your choice.
(a) Every square is a trapezoid.
True
False
(b) Some isosceles triangles are equilateral triangles.
True
False
(c) Every rhombus is a square.
True
False
(d) Every square is a rhombus.
True
False
(e) Some right triangles are equilateral triangles.
True
False
2. (9 points) Determine the number of degrees in each angle.
(a) The sum of the interior angles of an pentagon.
(b) The interior angle of a regular octagon.
(c) The exterior angle of a regular pentagon.
Page 2
3. (6 points) How many distinct line segments can be formed from seven points in a plane?
4. (6 points) Find the measures of angles r, s, and t in the figure below. where l k m.
Page 3
5. (6 points) The polyhedron below is a right hexagonal prism whose bases are regular
hexagons.
(a) (2 points) What face is parallel to the face IJDC?
(b) (2 points) What is the measure of the dihedral angle between face ABHG and face
ABCDEF ?
(c) (2 points) What is the measure of the dihedral angle between the face ABHG nad
face BCIH?
Page 4
6. (6 points) Consider the figure below.
(a) Which of the following three-dimensional objects could be used to make the shadow
show in (a)? More than one answer may be possible.
(b) Which of the following three-dimensional objects could be used to make the shadow
show in (b)? More than one answer may be possible.
Page 5
7. (6 points) Two prisms are sketched on dot paper in the figure below. Complete each of
the drawings by using dashed line segments for the hidden edges.
Page 6
8. (6 points) The following are pictures of stacks of solid cubes. In each case, determine
the number of cubes in the stack and the number of faces that are glued together.
Page 7
This page is for scratch work.
Page 8