Properties of plane figures

The triangle inequality

Types of exercises: can such a triangle exist?, the third side of a triangle.

Exercises are drawn at random from a large bank - every click gives a different set.

Solved: 0 of 10

1

Problem

Two sides of a triangle are 2 cm and 12 cm long, and the third side is a whole number of centimetres. What is the largest possible perimeter of this triangle?

2

Which three segments can form a triangle?

Below are four sets of three segment lengths.

3

Problem

Two sides of a triangle are 3 cm and 3 cm long, and the third side is a whole number of centimetres. How many lengths of the third side are possible?

4

Which three segments can form a triangle?

Below are four sets of three segment lengths.

5

Problem

Two sides of a triangle are 13 cm and 6 cm long, and the third side is a whole number of centimetres. What is the smallest possible perimeter of this triangle?

6

Which three segments can form a triangle?

Below are four sets of three segment lengths.

7

Problem

Two sides of a triangle are 2 cm and 11 cm long, and the third side is a whole number of centimetres. How many lengths of the third side are possible?

8

Which three segments can form a triangle?

Below are four sets of three segment lengths.

9

Problem

Two sides of a triangle are 9 cm and 3 cm long, and the third side is a whole number of centimetres. What is the smallest possible perimeter of this triangle?

10

Which three segments can form a triangle?

Below are four sets of three segment lengths.

This address is one particular set - everyone who opens it gets exactly the same exercises. Copy the link from the address bar and send it to the class. You can generate a new set at the top of the page.

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The triangle inequality - exercises with solutions (Properties of plane figures) | PhiBoard