Geometry / Mr. Hansen
12/15/2009

Name: _________________________

Test on Chapters 6, 7, and Beginning of 8
(100 Points, No Calculator Allowed)

      IMPORTANT! PLEASE READ! Zero points will be awarded for an algebra problem containing a wrong answer if your answer is not checked. For example, if a question asks you to find x if two supplementary angles have measures of x + 8 and 2x + 52, the correct answer is x = 40. If you wrote x = 80 (algebra error), you would receive NO CREDIT unless you also performed the check: Does (x + 8) + (2x + 52) = 180? No, since if you mistakenly think that x = 80, then x + 8 = 88 and 2x + 52 = 212, and 88 + 212  180. You would have to write that! You would have to write “300  180, NR” in order to receive any partial credit whatsoever.

 

Part I: Always, Sometimes, Never (5 pts. each)

In the small blank, write A if the statement is always true, S if sometimes true, or N if never true. NOTE: A SKETCH IS REQUIRED IN EACH CASE. ZERO POINTS FOR AN ANSWER WITH NO SKETCH, EVEN IF THE ANSWER IS CORRECT.

 

___1.

A square is a kite.

 

 

 

 

 

 

___2.

A parallelogram has perpendicular diagonals.

 

 

 

 

 

 

___3.

A trapezoid has three congruent sides.

 

 

 

 

 

 

___4.

The degree measures of an n-gon (n even, n < 25) add up to a multiple of 500.

 

 

 

 

 

 

___5.

The exterior angle measures of a convex n-gon add up to more than 360.

 

 

 

 

 

 

___6.

An equilateral quadrilateral is a rectangle.

 

 

Part II: Standard Proofs (20 pts. each)

Reproduce each proof from memory. A two-column format is required for the first one, but any reasonably legible approach you wish is acceptable for the second one.

 

7.

Prove that whenever two parallel planes are intersected by a third plane, the lines of intersection are parallel. Furnish a sketch, the “Given” and “Prove” statements, and a two-column proof.


 

8.

Prove that the angles of any triangle always add up to 180 degrees.


 

Part III: Short Answer (5 pts. each)

Partial credit is available only if you provide clear work.

 

 

9.

Why does Mr. Hansen believe that students should memorize proof #8 for a lifetime?

 

 

 

 

10.

Find the vertex angle of an isosceles triangle whose base angles are each 35 degrees.

 

 

 

 

 

 

 

 

 

 

 

 

11.

For the given regular octagon, compute .

 

 

 

 

 

12.

Find the indicated exterior angle of the triangle.

 



 

 

13.

What type of polygon has exactly 65 diagonals?

 

 

 

 

 

 

 

 

 

 

 

 

 

 

14.

Given: All gloos are bloos.
          All spoos are vroos.
          {Bloos}  {vroos} =
Could there be any gloos that are spoos?