Page 63 - NUMINO Challenge_B2

7 Angles

Basic Concepts Characteristics of Angles

Vertical angles are angles that are opposite to each other A
when two lines intersect, such as A and C, or B and D. BD
Vertical angles are equal.
C
Corresponding angles are angles that are in the same
position when one line intersects two lines, such as A and AD
E, B and F, C and G, or D and H. BC
EH
Alternate angles are angles that lie on opposite sides and FG
opposite ends of a transversal, such as B and H and C
and E. AD
BC
When two lines are parallel, corresponding angles and EH
alternate angles are equal. FG

(A E) (B F) (C G) (D H) (B H) (C E)

Example The types of angles that are formed when three lines intersect are
shown below.

1 Type 2 Types 3 Types

Find the types of angles that are formed when the three lines in the diagram
intersect.

Class Notes Since the triangle has a Since all angles of the
right angle, types of triangle are different,
Since two angles of an angles are formed.
isosceles triangle are types of angles are
equal, types of
angles are formed. formed.

60 NUMINO Challenge B2