Question

Which one of the following combinations of given parts does not determine the shape and size of indicated triangle?

• A. base angle and vertex angle; isosceles triangle
• B. vertex angle and the base; isosceles triangle
• C. the radius of the circumscribed Circle; equilateral triangle
• D. one arm and the radius of the inscribed circle; right triangle
• E. two angles and a side opposite one of them; scalene triangle

Answer 1

Answer: (A)

base angle and vertex angle; isosceles triangle

If base angles and vertex angles are known, then we can say the shape of the triangle but size cannot be determined from the angles.