Honors Geometry; 2/14

We spent some time today going over a couple more types of similar triangle proofs in preparation for tomorrow's test.  We also went over any homework questions the students had before getting started on the review assignment.


Assignment:  Chapter 7 test review


Chapter 7 Test

1.  5c2 / 7a2
2.  1/25
3.  2/9
4.  72
5.  2hs
6.  t + h / h
7.  g/s
8. g/s or h/t
9.  10
10.  10
11.  4/3
12.  triangle DAC
13.  AA for similar triangles
14.  3:5
15.  AC ; AD; CD
16.  15
17.  statements                               reasons
     given statements                       given
 angle K and angle S rt. angles      def. of perpendicular
angle K congruent to angle S        all right angles congruent
angle A congruent to angle A       reflexive
triangle AKT similar to tri. ASE    AA for similar triangles
AK/AB = AT/ AE                           if sim. triangles, corr. sides are proportional
AK/AT = AS / AE                           prop. of proportions

Test 27

1.  need CD = 10 or DE = 2
2.  AE parallel BD;  angle A congruent to angle B;  angle E congruent to angle D
3.  BC,  AE
4.  yes, by SSS for similar triangles
5.  proportional lengths and parallel lines
6.  a. yes
     b.  yes
     c.  no
     d.  yes
7.  x = 4
8.  x = 12
9.  x = 6.4
10.  x = 12.5
11.  x = 7.5
12.  x = 60

Test 26

1.  yes
2.  yes
3.  no
4.  yes
5.  no
6.  SAS for sim. triangles
7.  AA for sim. triangles
8.  none
9.  none
10.  AA for sim. triangles
11.  SSS for sim. triangles
12.  1.  angle 1 and angle 2 are complementary
            angle 2 and angle 3 are complementary

       2.  complements of the same angle are congruent
       3.  reflexive
       4.  AA for sim. triangles
       5.  corr. sides of sim. triangles are proportional
       6.  cross multiplication

Similarity Proofs

1,                       statements                            reasons
     IE parallel to VO                                     given
    angle D cong. to angle D                          reflexive
    angle I cong. to angle V                          if lines II, then corr. angles congruent
   tri. DIE similar to tri. DVO                      AA for similar triangles
   ID/IV = ED/EO                                        corr. sides of sim. triangles proportional


2.                 statements                                reasons
       AE parallel BD                                     given
      angle C cong. to angle C                       reflexive
      angle B cong. to angle A                       if lines parallel, corr. angles congruent
     tri. CBD sim. to tri. CAE                       AA for sim. triangles


3.             statements                                  reasons
       AB parallel to DC                                given
       angle 1 congruent to angle 2               vertical angles congruent
      angle ABE cong. to angle CDE           if lines parallel, AIA congruent
      tri. AEB similar to tri. CED                 AA for similar triangles