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# Congruent Triangles: Triangular Breeds Quiz

Think you’ve got your head wrapped around Congruent Triangles? Put your knowledge to the test. Good luck — the Stickman is counting on you!
Q. Which of the following statements is true?

The sum of all interior angles in a triangle is equal to the sum of all the exterior angles of the triangle.
The sum of all exterior angles in a triangle is always equal to two times the sum of the interior angles in the triangle.
The sum of all interior angles in a triangle varies depending on the triangle.
The product of all the interior angles in a triangle is always 180.
None of the above.
Q. Under what circumstances are equilateral triangles acute?

Always
Only when the side lengths of the equilateral triangles are less than 90
Only when all the interior angles of the equilateral triangle add up to less than 180°
Only when the side lengths are smaller than the angle measurements
Never
Q. Under what circumstances are isosceles triangles equilateral?

Always
Only when two sides of the triangle are congruent to each other
Only when any two sides of the triangle are congruent to each other
Only when the isosceles triangle is right
Never
Q. According to the Exterior Angle Theorem, which of the following is true?

All exterior angles in a triangle add up to 180°
The measure of any given exterior angle equals the sum of the measures of all the interior angles
The measure of any given exterior angle equals the sum of the measures of any two interior angles
The measure of any given exterior angle equals the sum of the measures of the two remote interior angles
Exterior angles are the supplements to interior angles
Q. Which is true about scalene triangles specifically?

They are always acute
Their side lengths differ in length
Their interior angles don't always add up to 180°
They are always equiangular.
They are always obtuse
Q. A triangle has angle measurements of 80° and 92°. What is the measurement of the final angle?

28°
188°
Such a triangle does not exist
Q. Which of the following is false?

A triangle can have a maximum of two obtuse angles
A triangle that is equilateral is also equiangular
An acute triangle must have three acute angles
A right triangle must have a minimum of one 90° angle
All of the above
Q. If one of the exterior angles of a triangle equals 73° and one if its interior angles is 29°, what are the measures of its three angles?

29°, 44°, 73°
29°, 73°, 78°
29°, 44°, 107°
29°, 73°, 107°
29°, 78°, 107°
Q. If two of the interior angles of a triangle add up to 45°, what kind of triangle must it be?

Acute
Scalene
Isosceles
Obtuse
Right
Q. An isosceles triangle can never be which of the following?

Scalene
Equilateral
Obtuse
Right
All of the above