Question

Which of the following triangles are impossible to draw? Choose all that apply.

A. a triangle with angles of 30°, 45°, and 115°
B. a triangle with two right angles
C. a triangle with sides of 2 units, 3 units, and 4 units
D. a triangle with sides of 3 inches, 4 inches, and 8 inches
E. an obtuse equilateral triangle
F. a right scalene triangle

Answer 1

Impossible: A, B, D, E

Explanation:

A. 30 + 45 + 115 = 190; sum is more than 180°. IMPOSSIBLE

B. 90 + 90 + x = 180; x = 0; third angle has 0° measure. IMPOSSIBLE

C. Each side length is between the sum and difference of the other two sides' lengths. POSSIBLE

D. 3 + 4 < 8. IMPOSSIBLE

E. An equilateral triangle has 3 congruent angles measuring 60° each. IMPOSSIBLE

F. For example, a triangle with lengths 3, 4, 5. POSSIBLE