Section 4.2 Angle Measures of triangles
SWBAT find angle measures in triangles
WARM UP
Classify each triangle by its sides and angle measures.
Triangle Sum Theorem
The sum of the measures of the angles of a triangle is _____________
Corollary to the Triangle sum theorem
The acute angles of a right triangle are __________________.
Finding angle measures of a right triangle
Given m<A=43° and m<B=85°, find the m<C
ABC and ABD are right triangles. Suppose m<ABD=35°
YOU Try
Interior and exterior angles
When the three sides of the triangle are extended other angles are formed.
the three original angles are
The angles that are adjacent
the ________________________.
to the interior angles are the
______________________.
Exterior angle theorem
The measure of an exterior angle of a triangle is equal to the
____________________________________________________.
Example: Given m < A = 58° and
m < C = 72°, find m < 1
Find the value of x.
YOU TRY
Using Algebra
Find the value of x
You try
Find the value of x