# Maths

## Maths Friday 12th February 2021 12.02.21

Well done this week.

Now we can start to look at angles within shapes.

We are going to begin by looking at triangles.

The angles within a triangle add up to exactly 180º.

Look at the equilateral triangle below. You should notice that all 3 angles are 60°. 60° + 60° + 60° = 180°

Now lets have a look at working out missing angles inside a triangle.

To do this we need to complete 2 steps.

1. Add the angles we do know
2. Subtract the answer from 180

Lets have a look at a few examples. Step 1

70° + 50° = 120°

Step 2

180° - 120° = 60° Step 1

68° + 47° = 115°

Step 2

180° - 115 = 65°

Now lets have a look at an Isosceles Triangle

Isosceles triangles have 2 angles the same and 1 different.

To work out the angle is an isosceles triangle we follow 2 different steps.

1. Subtract known angle from 180

Lets have a look at a few examples. Step 1

Subtract known angle from 180

180° - 116° = 64°

Step 2

64° ÷ 2 = 32° Step 1

Subtract known angle from 180

180° - 56° = 124°

Step 2