Flashcards in Lines And Angles Deck (19):

1

## What kinds of angles are there?

###
Acute angles

Right angles

Obtuse angles

Straight angles

Reflex angles

Revolution

2

## What is an acute angle?

### An angle that is greater than 0° but smaller than 90°

3

## What is a right angle?

### An angle of 90°

4

## What is an obtuse angle?

### It is greater than 90° but smaller than 180°

5

## What is a straight angle?

### An angle of 180°

6

## What is a reflex angle?

### Greater than 180° but smaller than 360°

7

## What is a revolution?

### An angle of 360°

8

## What are adjacent angles?

### Two angles with a common vertex (corner) that lie next to each other.

9

## What are complementary angles?

### Angles with a sum of 90°

10

## What are supplementary angles?

### Angles that add up to 180°

11

## What are angles on a straight line?

### They are supplementary i.e they add up to 180°

12

## What are vertically opposite angles?

### They are angles made up of the same two lines. They are equal.

13

## What are angles around a point?

### They are angles that surround a common vertex. They add up to 360°

14

## What are the three parallel line theorems?

###
Corresponding angles

Alternate angles

Co-interior angles

15

## What are corresponding angles?

### When the parallel lines that make up two angles form an 'F' shape, those two angles are equal.

16

## What are alternate angles?

### When the parallel lines that make up two angles form a 'Z' shape, those two angles are equal.

17

## What are co-interior angles?

### When the parallel lines that make up two angles form a 'U' shape, those two angles are supplementary.

18

## What is important to remember when using parallel line theorems?

###
Always make sure that the lines that you are using are actually parallel

Always state the parallel lines that you used in your reason

19