Basic Mathematics for College Students

c. Name the base angles.

d. Which side is opposite?

e. What is the vertex angle?

f. Which angle is opposite side?

g. Which two angles are congruent?

19. Refer to the triangle below.

a. What do we know about and?

b. What type of triangle is?

20. a. Find the sum of the measures of the angles of
    , shown in figure (a).
    b. Find the sum of the measures of the angles of
    , shown in figure (b).
    c. What is the sum of the measures of the angles of
    anytriangle?

NOTATION

Fill in the blanks.

21. The symbol means.


22. The symbol means the of angle.

Refer to the triangle below.

23. What fact about the sides of do the tick
    marks indicate?


24. What fact about the angles of do the tick
    marks indicate?

C

B

A

ABC

ABC

m(A) A



53 °

95 ° 32 °

J

K L

(a)

57 °

59 °

64 °

C

E

D

(b)

CDE

JKL

57 ° 57 °

66 °

F

E G

EFG

EF GF

XY

X

GUIDED PRACTICE

For each polygon, give the number of sides it has, give its name,

and then give the number of vertices that it has.See Example 1.

25. a. b.


26. a. b.


27. a. b.


28. a. b.

Classify each triangle as an equilateral triangle, an isosceles

triangle, or a scalene triangle.See Objective 2.

29. a. b.


30. a. b.


31. a. b.


32. a. b.

1.4 in.

1.7 in.

20 cm 1.8 in.

15 cm

20 cm

4 in.

3 in. 5 in.

2 in.

2 in. 2 in.

55 °

55 °

3 ft 2 ft

4 ft

9.3 Triangles 743