Year 9 Pythagoras' Theorem Worksheet — Level 2 — Practice Set 3 — Answers
Answer sheet with worked solutions for the Year 9 pythagoras' theorem worksheet.
Success TutoringWorksheetsAnswer sheetYear 9 · Mathematics · Pythagoras' TheoremYear 9 Pythagoras' Theorem Worksheet — Level 2 — Practice Set 3 — Answers
Use c² = a² + b², where c is the hypotenuse. Show your working.
1.A right-angled triangle has a hypotenuse of 5 cm and one shorter side of 3 cm. Find the other side.
Answer: 4 cm
- b2 = 52 − 32
- b2 = 25 − 9 = 16
- b = √16 = 4
2.A right-angled triangle has shorter sides of 6 cm and 8 cm. Find the length of the hypotenuse.
Answer: 10 cm
- c2 = 62 + 82
- c2 = 36 + 64 = 100
- c = √100 = 10
3.A right-angled triangle has a hypotenuse of 25 cm and one shorter side of 15 cm. Find the other side.
Answer: 20 cm
- b2 = 252 − 152
- b2 = 625 − 225 = 400
- b = √400 = 20
4.Find the hypotenuse of a right-angled triangle with shorter sides 3 m and 3 m. Give your answer to 1 decimal place.
Answer: 4.2 m
- c2 = 32 + 32 = 18
- c = √18 ≈ 4.2
5.A right-angled triangle has a hypotenuse of 13 cm and one shorter side of 5 cm. Find the other side.
Answer: 12 cm
- b2 = 132 − 52
- b2 = 169 − 25 = 144
- b = √144 = 12
6.Find the hypotenuse of a right-angled triangle with shorter sides 4 m and 4 m. Give your answer to 1 decimal place.
Answer: 5.7 m
- c2 = 42 + 42 = 32
- c = √32 ≈ 5.7
7.Find the hypotenuse of a right-angled triangle with shorter sides 10 m and 11 m. Give your answer to 1 decimal place.
Answer: 14.9 m
- c2 = 102 + 112 = 221
- c = √221 ≈ 14.9
8.Find the hypotenuse of a right-angled triangle with shorter sides 7 m and 6 m. Give your answer to 1 decimal place.
Answer: 9.2 m
- c2 = 72 + 62 = 85
- c = √85 ≈ 9.2
Marking tips
- Give credit for correct method even when the final answer slips — the working shows where the thinking went right.
- For open-ended tasks, use the success criteria as a checklist rather than looking for one "right" answer.
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