1.3.1
Angles on a Straight Line
Angles on a Straight Line
Angles on a Straight Line
Angles on a straight line always add up to 180°. You can use this information to solve straight line problems.


Angles on a straight line add to 180°
Angles on a straight line add to 180°
- You know that angles on a straight line add up to 180 degrees.
- So you need to take the angle away from 180 degrees to work out the missing angle.
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Work out the answer
Work out the answer
- 180 - 110 = 70
- So the missing angle is 70°
1Angles
1.17 Facts About Angles
1.2Identify the Angle
1.3Angles on a Straight Line
1.4Angles in a Circle
1.5Angles in Triangles
2Fractions
2.1Simplifying Fractions
2.2Improper Fractions & Mixed Numbers
2.3Fractions of Numbers
2.4Expressing Shaded Areas as Fractions
3Time
4Prime Numbers
4.1Prime Numbers
5Probability
6Ratio
6.1Ratios
7Sequences
7.1Constant Sequences
7.2Doubling & Halving Sequences
7.3Alternating Patterns & Two-Step Sequences
7.4Two-Step Patterns
7.5The nth Term
8Area & Perimeter
8.1Perimeter of a Quadrilateral
8.2Area of a Quadrilateral
8.3Area of a Triangle
Jump to other topics
1Angles
1.17 Facts About Angles
1.2Identify the Angle
1.3Angles on a Straight Line
1.4Angles in a Circle
1.5Angles in Triangles
2Fractions
2.1Simplifying Fractions
2.2Improper Fractions & Mixed Numbers
2.3Fractions of Numbers
2.4Expressing Shaded Areas as Fractions
3Time
4Prime Numbers
4.1Prime Numbers
5Probability
6Ratio
6.1Ratios
7Sequences
7.1Constant Sequences
7.2Doubling & Halving Sequences
7.3Alternating Patterns & Two-Step Sequences
7.4Two-Step Patterns
7.5The nth Term
8Area & Perimeter
8.1Perimeter of a Quadrilateral
8.2Area of a Quadrilateral
8.3Area of a Triangle
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