Geometry and TrigonometryMediumApex angle from a base angle
Geometry and Trigonometry practice question
In an isosceles triangle, each of the two equal angles measures 52°. What is the measure, in degrees, of the third angle?
Answer: 76
180 − 52 − 52 = 76.
Common wrong answers
- If you answered 38
- 38 is 90 − 52, treating the triangle as right-angled.
- If you answered 52
- 52 is a base angle; the third angle differs.
- If you answered 128
- 128 is 180 − 52, subtracting only one base angle.
More Geometry and Trigonometry questions
- Medium
In a 45°-45°-90° right triangle, each leg has length 5. What is the length of the hypotenuse? - Medium
A cylinder has a radius of 3 and a height of 10. What is its volume? (Use V = πr²h.) - Medium
In a right triangle, the side opposite angle θ has length 3 and the hypotenuse has length 5. What is sin θ? - Medium
Two triangles are similar with a ratio of 2 to 3. A side of the smaller triangle measures 8. What is the lengt… - Medium
What is the distance between the points (1, 2) and (4, 6) in the coordinate plane? - Medium
A circle has a radius of 6. What is the area of a sector with a central angle of 60°?
Not affiliated with the College Board. SAT is a trademark of the College Board.