Foundations of Mathematics 11
Unit 2 Properties of Angles and Triangles
Lesson Two Practice Assignment
Angle Properties in Triangles
1. Find the missing angles and give a reason for your answer.
a)
b)
c)
1 =
2 =
3 =
4 =
d)
Lesson 2
Page 1 of 7
Unit 2
Foundations of Mathematics 11
Unit 2 Properties of Angles and Triangles
e)
f)
g)
h)
i)
1 =
2 =
Lesson 2
Page 2 of 7
Unit 2
Foundations of Mathematics 11
Unit 2 Properties of Angles and Triangles
j)
k)
ANSWERS
1a) 1  65 cointerior and angle bisector
2  115 cointerior angles
1b) 1  120 angle sum of triangle and angles opp = sides are =
2  60 supplementary angles
1c) 1  70 angles opp = sides are =
2  70 alternate interior angles
3  65 angles opp = sides are =
4  45 angles on a line
1d) 1  70 supplementary angles and angle sum of triangle
2  70 vertically opposite angles
1e) 1  35 cointerior angles
1f) 1  65 alternate interior angles and angles opp = sides are =
2  115 supplementaryangles
1g) 1  70 angles opp = sides are =
2  60 angles on a line
1h) 1  37.5 cointerior and vertically opposite
2  37.5 alternate interior
1i) 1  26.25 angles opp = sides are = and supplementary
2  52.5 angles opp = sides are =
1j) 1  45 angles opp = sides are =
2  65 angles on a line
3  50 angle sum triangle
1k) 1  50 angle sum triangle
2  70 alternate interior angles
3  30 angle sum triangle
Lesson 2
Page 3 of 7
Unit 2