Pythagoras Basics
Solve It
Spot the mistake
NAPLAN Challenge
Think First
100

What is Pythagoras’ theorem?

a2+b2=c2

100

Find the hypotenuse:

3, 4, ?

5

100

A student says:

32+42=12

What mistake did they make?

They added 3 and 4 instead of squaring first

100

Josh completes 4 laps of a 3 km track.

Distance travelled?

12 km

100

When finding the hypotenuse, do we:

  • add the squares
  • or subtract the squares?

Add the squares

200

What is the longest side of a right-angled triangle called?

Hypotenuse

200

Find the short side:

?, 12, 13

5

200

Miss Pollard says:

52+122=169

c=169

What did she forget?

Square root

200

A fishing rod costs $80 and is 25% off.

Discount amount?

$20

200

When finding a short side, do we:

  • add the squares
  • or subtract the squares?

Subtract the squares

300

What type of triangle can use Pythagoras’ theorem?

Right-angled triangle

300

Find the hypotenuse:

8, 15, ?

17

300

Phoenix solves:

x2+82=102

x2=164

What mistake did he make?

100−64 not plus

300

A rectangle has length 9 cm and width 5 cm.

Perimeter?

28 cm

300

A triangle has sides:

  • 5 cm
  • 12 cm
  • 13 cm

Which side is the hypotenuse?

13 cm

400

Which side is always labelled c?

Longest side / hypotenuse

400

Find the short side:

?, 24, 25

7

400

Why is the order important when finding the short side?

Must subtract smaller square from hypotenuse square / you will end up with a negative

400

A boat travels 6 km every hour.

How far in 5 hours?

30 km

400

Why can’t the hypotenuse be a smaller number than the other sides?


Because it is always the longest side

500

Why is the hypotenuse always the largest side?

Because it is opposite the largest angle (90°)

500

Find the hypotenuse:

9, 40, ?

41

500

Amaylia labels the shortest side as c.

Why is this incorrect?

c must be the hypotenuse

500

A campsite has 36 people.
Each tent fits 4 people.

How many tents are needed?

9

500

A triangle has sides:

  • 6
  • 8
  • 9

Can this be a right-angled triangle? Explain. 

No

Because:

62+82=100

√ 100=10

not 9.