Transcript Parallel Lines and the Triangle Angle

Blue – 2/23/2015
Gold – 2/24/2015
1.
1 2 3
2.
4
5
3.
Name 2 pair of alternate interior angles
5 & 3
and
4 & 1
What is the sum of m1 + m2 + m3?
180°
If m4 = 65° and m5 = 50°, what is
m2? (hint: the sum of triangle angles =
180)
65°
Solve each equation.
4. 30 + 90 + x = 180
60
5. 55 + x + 105 = 180
70
6. x+ 58 = 90
32
The sum of the angle measures in a triangle
equal 180°
1
3
2
1 + 2 + 3 = 180°
1.
1
2.
117
33
3.
33
1
57
52.2
44.7
1
Acute: A triangle in which all 3 angles are less than 90˚.
G
76
57
H
47
I
Obtuse:
A triangle in which one and only one
angle is greater than 90˚& less than 180˚
A
44
28 108 C
B
Right: A triangle in which one and only one angle is 90˚
A
56
90
34
C
B
Equiangular: A triangle in which all 3 angles are the same measure.
B
60
A
60
60
C

Equilateral triangle: A triangle with
three congruent (equal) sides and three
equal angles
These marks indicate equality.

Isosceles triangle: A triangle with at
least two congruent (equal) sides

Right triangle: Has only one right angle
(90 degrees)
This box indicates a right angle or
a 90-degree angle.

Scalene triangle: A triangle that has no
congruent (equal) sides

Classify each type of triangle based on
sides and angles.
50
Right &
Scalene
60
4
100
2
60
Equilateral &
Equilangular
Scalene
& Obtuse
30
80
1
60
30
3
60
50
50
Isosceles
& Acute
The measure of an exterior angle in a
triangle is the sum of the measures of
the 2 remote interior angles
exterior
angle
remote
interior
angles
A = C + D
The measure of an exterior angle in a
triangle is the sum of the measures of
the 2 remote interior angles
remote
interior
angles
exterior
angle
2
1
3
4 = 1 + 2
4