Download Warm-Up Exercises

Warm-Up
Exercises
Bell Work
For 1-3, Classify each triangle by its sides.
1. 2 cm, 2 cm, 2 cm
2. 7 ft, 11 ft, 7 ft
3. 9 m, 8 m, 10 m
4. In ∆ABC, if m
A = 70º and m B = 50º, what is m C?
5. In ∆DEF, if m D = m E and m
the measure of D and E
F = 26º, What are
Warm-Up
Exercises
Notes
Base Angles Theorem
If two sides of a triangle are congruent, then the angles opposite
them are congruent.
Converse of Base Angles Theorem
If two angles of a triangle are congruent, then the sides opposite
them are congruent.
Warm-Up1Exercises
EXAMPLE
Apply the Base Angles Theorem
In
DEF, DE
DF . Name two congruent angles.
Warm-Up
Exercises
GUIDED
PRACTICE
for Example 1
Copy and complete the statement.
1.
If HG
HK , then
?
? .
Warm-Up
Exercises
GUIDED
PRACTICE
for Example 1
Copy and complete the statement.
2.
If
KHJ
KJH, then ?
? .
Warm-Up
Exercises
Notes
Corollary to the Base Angles Theorem
If a triangle is equilateral, then it is equiangular.
Corollary to the Converse of Base Angles Theorem
If a triangle is equiangular, then it is equilateral.
Warm-Up2Exercises
EXAMPLE
Find measures in a triangle
Find the measures of
P,
Q, and
R.
Warm-Up
Exercises
GUIDED
PRACTICE
3.
for Example 2
Find ST in the triangle at the right.
Warm-Up
Exercises
GUIDED
PRACTICE
4.
for Example 2
Is it possible for an equilateral triangle to
have an angle measure other than 60°?
Explain.
Warm-Up3Exercises
EXAMPLE
Use isosceles and equilateral triangles
ALGEBRA
Find the values of x and y in the diagram.
Warm-Up4Exercises
EXAMPLE
Solve a multi-step problem
Lifeguard Tower
In the lifeguard tower, PS
and
QPS
PQR.
QR
a.
What congruence postulate
can you use to prove that
QPS
PQR?
b.
Explain why
c.
Show that
PQT is isosceles.
PTS
QTR.
Warm-Up
Exercises
GUIDED
PRACTICE
5.
for Examples 3 and 4
Find the values of x and y in the diagram.
Daily
Homework
Warm-Up
Exercises
Quick
CheckQuiz
Find the value of x.
Find the value of x.
1.
2.
3. If the measure of vertex angle of an isosceles
triangle is 112°, what are the measures of the
base angles?
Warm-Up
Exercises
For Tomorrow
Homework
HW: 4.8 (pg. 267-269) # 8,12,16,24,34,38,40,41