Work through the levels in order. Type your answer and press Check — open the worked solution if you get stuck. Answers like -6, 3/4 or 0.25 are typed exactly as shown. A ⭐ Bonus Challenge at the end is extra credit — skip it if the rest was hard work.
Level 1 · Warm-up
1 Two straight lines cross. One angle is 60°. What is the angle opposite it?
Show worked solution
It is also 60°.
2 Two straight lines cross. One angle is 70°. Write the angle opposite it, and the angle beside it.
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Opposite 70°, beside 110°.
3 Two straight lines cross. One angle is 110°. How many degrees is the angle beside it on the straight line?
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70°.
Level 2 · Core
4 Two straight lines cross. One angle is 130°. What is the angle beside it?
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50°.
5 Two straight lines cross, making an angle of 55°. Write the four angles in order round the crossing, starting from the 55°.
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55°, 125°, 55°, 125°. They add to 360 ✓.
6 Two straight lines cross. Three of the four angles are 40°, 140° and 40°. How many degrees is the fourth?
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140°.
Level 3 · Challenge
7 Two straight lines cross. One of the angles is 65°.1 c = 65°.
2 b = 115°.
3 b = 65°.
Which statements are correct?
2 b = 115°.
3 b = 65°.
Which statements are correct?
Show worked solution
c is opposite so 65° (1 ✓); b = 180 − 65 = 115° (2 ✓), not 65° (3 ✗). 1 and 2.
8 Angles a, b and c sit on a straight line, with a = 40° and b = 110°. The angle opposite a, across the crossing point, is called d.
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c = 30°; d is opposite a, so d = 40°.
9 Two straight lines cross so that all four angles are equal. How many degrees is each angle?
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90° — the lines are perpendicular.