Triangle Properties and Theorems

This video tutorial covers the basics of triangles, including types such as acute, obtuse, right, scalene, isosceles, and equilateral. It explains the isosceles triangle theorem and its converse, and demonstrates solving triangle-related problems. The video also discusses congruent figures and the importance of corresponding parts in geometry.

Which type of triangle has all angles less than 90 degrees?

• Scalene

• Right

• Obtuse

• Acute

In a scalene triangle, how many sides are of equal length?

• Two

• One

• All

• None

According to the isosceles triangle theorem, if two sides of a triangle are congruent, what can be said about the opposite angles?

• They are obtuse

• They are right angles

• They are congruent

• They are different

If two angles of a triangle are congruent, what can be inferred about the opposite sides?

• They are parallel

• They are congruent

• They are perpendicular

• They are unequal

What is the sum of the interior angles of any triangle?

• 360 degrees

• 270 degrees

• 180 degrees

• 90 degrees

In an equilateral triangle, what is true about the angles?

• All angles are different

• All angles are right angles

• All angles are obtuse

• All angles are equal

What does it mean for a triangle to be equiangular?

• One angle is 90 degrees

• Two sides are equal

• All angles are equal

• All sides are different

What must be true for two figures to be congruent?

• Different shape, different size

• Same shape, same size

• Different shape, same size

• Same shape, different size

What are corresponding parts in congruent figures?

• Parts that are different

• Parts that are parallel

• Parts that match

• Parts that are perpendicular

If triangle ABC is congruent to triangle DEF, which angle corresponds to angle A?

• Angle F

• None of these

• Angle E

• Angle D