Exact or Decimal?
What is an exact answer?
An answer that is not rounded
Find the hypotenuse:
Formula + Answer
Pythagoras + Add + 5
Solve:
17
(full working required)
Complete:
8, 15, ___
17
Write in exact form:
42+72
√65
Find the missing side:
Formula + Answer
Short side → Subtract → 5
Solve:
7
(full working required)
Complete:
20, 21, ___
29
Round:
8.3768
to 2 decimal places.
8.38
A triangle has:
What operation should you use?
a2 = c2 - b2
Find the diagonal:
10
(full working required)
A student says:
“You always add in Pythagoras.”
Explain why this is incorrect.
You subtract when finding a shorter side.
A triangle has shorter sides:
Find the hypotenuse:
exact form: √106
decimal approximation: 10.30
A student writes:
72+252=x2
Explain the mistake.
25 is the hypotenuse and must come first when finding a short side.
Do these form a right-angled triangle?
Yes
(full working required)
A triangle has:
Find the missing side.
9
A student writes:
√65 = 8
Explain why this is incorrect.
8 is rounded and not exact form.
A triangle has:
Should you:
Explain why.
Add, because we are checking if it satisfies Pythagoras’ theorem.
A ladder reaches:
Find ladder length WITH FULL WORKING.
13 m
Without fully solving:
Explain why:
do NOT form a right-angled triangle.
15–20–25 is the known triad, not 24.