Question

for each triangle, check all that apply. triangle a triangle b triangle c triangle d scalene scalene scalene scalene isosceles isosceles isosceles isosceles equilateral equilateral equilateral equilateral

Explanation:

Triangle A

• All angles are \(60^{\circ}\). By the definition of an equilateral triangle (all angles equal and all sides equal), it is equilateral. Since an equilateral triangle is also a special case of an isosceles triangle (at least two sides equal), it is also isosceles.

Triangle B

• All angles (\(45^{\circ},60^{\circ},75^{\circ}\)) are different. By the definition of a scalene triangle (all angles different and all sides different), it is scalene.

Triangle C

• Two sides are equal (\(7 = 7\)). By the definition of an isosceles triangle (at least two sides equal), it is isosceles.

Triangle D

• Two sides are equal (\(8 = 8\)). By the definition of an isosceles triangle (at least two sides equal), it is isosceles.

Answer:

• Triangle A: Isosceles, Equilateral
• Triangle B: Scalene
• Triangle C: Isosceles
• Triangle D: Isosceles