S.5

Base Angles of Isosceles Triangles

Q4 · Apr–Jun

Use the vertex angle of an isosceles triangle to find its two equal base angles.

Level
Medium
Problems
Daniel Math Academy · Grade 5 Math

Base Angles of Isosceles Triangles

Skill S.5 · Triangles · ★★☆ Medium · Quarter 4

Name
 
Date
 
Score/ 6

Ticks mark equal sides. The angles opposite equal sides are equal.

Example
40°??
? =

Think: The two base angles are equal and share what is left of : .

  1. 1
    40°??
    The triangle is isosceles. Find each base angle. 
  2. 2
    20°??
    The triangle is isosceles. Find each base angle. 
  3. 3
    140°??
    The triangle is isosceles. Find each base angle. 
  4. 4
    50°??
    The triangle is isosceles. Find each base angle. 
  5. 5
    120°??
    The triangle is isosceles. Find each base angle. 
  6. 6
    30°??
    The triangle is isosceles. Find each base angle. 
Daniel Math Academy · danielmath.comWorksheet #dwuwvak · Page 1 / 2
Daniel Math Academy · Grade 5 Math

Answer Key

S.5 Base Angles of Isosceles Triangles · ★★☆ Medium

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