Shapes, Lines, Acute, Obtuse Right Angles

Which of the following is a right angle?

• 30°

• 60°

• 90°

• 120°

Which angle appears to be a right angle?

Identify the type of angle formed by the hands of a clock at 3:00.

• Acute

• Right

• Obtuse

• Straight

How many right angles does this shape have?

HOW MANY RIGHT ANGLES DO YOU SEE IN THIS SHAPE?

• 1

• 2

• 3

• 4

• parallel lines
• perpendicular lines
• intersecting lines
• a ray

Name the following triangle by its angles.

• scalene triangle

• right triangle

• obtuse triangle

• acute triangle

Does this shape have a right angle?

• Yes

• No

The shapes above were sorted into two groups. Which of the following are two possible titles for those groups?

• Shapes with Right Angles, Shapes with No Angles

• Shapes with All Equal Sides, Shapes with Right Angles

• Shapes with Right Angles, Shapes with Parallel Sides

• Shapes with All Equal Sides, Shapes with Obtuse Angles

An acute triangle is

• A triangle with 1 obtuse angle

• A triangle with all sides the same length

• A parallelogram

• A triangle with 3 acute angles