Geometry and TrigonometryEasy–MediumBase angles from a vertex angle
Geometry and Trigonometry practice question
An isosceles triangle has a vertex angle of 100°. What is the measure, in degrees, of each base angle?
Answer: 40
The two base angles are equal and total 80: 40 each.
Common wrong answers
- If you answered 50
- 50 halves 100 instead of 80.
- If you answered 80
- 80 is the total of the two base angles.
- If you answered 100
- 100 is the vertex angle.
More Geometry and Trigonometry questions
- Easy–Medium
A circle has a radius of 6. What is its area? (Use A = πr².) - Easy–Medium
A right triangle has legs of length 6 and 8. What is the length of the hypotenuse? - Easy–Medium
A circle has a radius of 5. What is its circumference? (Use C = 2πr.) - Easy–Medium
What is the midpoint of the segment joining the points (2, 3) and (8, 11)? - Easy–Medium
What is the measure, in degrees, of angle B? - Easy–Medium
What is the area, in square centimeters, of the trapezoid?
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