Triangle Review - 7th Grade

Would side lengths of 4, 3, and 7 form a triangle? Why or why not?

• Yes, because the sum of any two sides is greater than the third side.

• No, because 3 + 4 is not greater than 7.

• Yes, because 4 + 7 is greater than 3.

• No, because 4 + 7 is equal to 11, which is not a valid triangle.

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

• 90 degrees

• 180 degrees

• 360 degrees

• 120 degrees

A triangle with two equal sides is called a ______________ triangle.

• equilateral

• isosceles

• scalene

• right

Give an example of three angles that would NOT form a triangle.

• 30°, 60°, 90°

• 50°, 60°, 80°

• 70°, 80°, 50°

• 40°, 50°, 100°

Name this triangle: It has one angle that is exactly 90 degrees.

• acute triangle

• obtuse triangle

• right triangle

• isosceles triangle

A triangle with one angle greater than 90 degrees is called a ______________ triangle.

• acute

• right

• obtuse

• equilateral

If a triangle has sides of lengths 3, 4, and 5, what type of triangle is it?

• scalene

• isosceles

• equilateral

• right

Classify this triangle based on its angles: All angles are less than 90 degrees.

• obtuse

• right

• acute

• scalene

A ______________ triangle has No equal sides.

• isosceles

• equilateral

• scalene

• right

Will these angles form a triangle? If so, what type.

20, 140, 20

• Yes! It would form an Obtuse Isosceles Triangle because one angle is obtuse and two angles have the same measure!

• No, these angles cannot form a triangle.

• Yes! It would form an Acute Scalene Triangle because all angles are different.

• Yes! It would form a Right Triangle because one angle is 90 degrees.