# Right angle - Examples, Exercises and Solutions

## Definition of Right Angle

A right angle is one of the types of angles that we will encounter during engineering studies.

A right angle is one that measures $90°$. We generally mark it with a small square at the area where it is formed.

Right angles can appear in triangles, squares, rectangles, and other geometric shapes with angles of $90°$ degrees.

To which of the 4 angles shown in the figure does the description of the right angle apply?

The correct answer is A) 90°

## Practice Right angle

### Exercise #1

True or false?

One of the angles in a rectangle may be an acute angle.

### Step-by-Step Solution

One of the properties of a rectangle is that all its angles are right angles.

Therefore, it is not possible for an angle to be acute, that is, less than 90 degrees.

False

### Exercise #2

True or false?

The sum of two acute angles can be greater than 180 degrees?

False.

### Exercise #3

Does the drawing show an adjacent angle?

Not true

### Exercise #4

Does the drawing show an adjacent angle?

Not true

### Exercise #5

Does the drawing show an adjacent angle?

Not true

### Exercise #1

Does the drawing show an adjacent angle?

Not true

### Exercise #2

Does the drawing show an adjacent angle?

Not true

### Exercise #3

Does the drawing show an adjacent angle?

Not true

### Exercise #4

If the two adjacent angles are not equal to each other, then one of them is obtuse and the other acute.

True

### Exercise #5

Does the drawing show an adjacent angle?

True

### Exercise #1

Which of the following angles is a plane angle?

### Exercise #2

Which figure shows a right angle?

### Exercise #3

Which of the following angles is obtuse?

### Exercise #4

Which of the following angles is obtuse?