Worksheet: Perimeter of a Triangle

In this worksheet, we will practice finding the perimeter of a triangle as a value and as an algebraic expression by adding its side lengths.

Q1:

What is the perimeter of this triangle?

Q2:

Write an expression in terms of , for the perimeter in cm, of the isosceles triangle shown below.

• A cm
• B cm
• C cm
• D cm

Q3:

The base of an isosceles triangle is 4 more than the length of one of the equal sides. Let be the length of one of the equal sides and write an equation for , the perimeter of the triangle.

• A
• B
• C
• D
• E

Q4:

Calculate the perimeter of an equilateral triangle whose side length is 3.39 cm.

Q5:

In the parallelogram shown, and . What is the perimeter of ?

Q6:

If the perimeter of this triangle is 234, find the length of the third side.

Q7:

The perimeter of a triangular piece of land is 166 meters. Find the length of its third side if the sum of two of its sides is 102 meters.

Q8:

The side length of an equilateral triangle is units and its perimeter is units. Write the mathematical relation between and .

• A
• B
• C
• D
• E

Q9:

Given that and , find the perimeter of to the nearest hundredth, if needed.

Q10:

Find the perimeters of and .

• A perimeter of , perimeter of
• B perimeter of , perimeter of
• C perimeter of , perimeter of
• D perimeter of , perimeter of

Q11:

Find the perimeter of .

Q12:

is a triangle where , and . Find the perimeter of the triangle giving the answer to the nearest centimetre.

Q13:

is a triangle, where cm, cm, and the perimeter is 124 cm. Find the lengths of and giving the answers to the nearest centimetre.

• A ,
• B ,
• C ,
• D ,
• E ,

Q14:

The perimeter of a triangle is given by cm. The lengths of two of its sides are cm and cm. Express the length of the third side in terms of .

• A cm
• B cm
• C cm
• D cm

Q15:

In triangle we have and . If the perimeter of the triangle is 46.2, what is the length of ?

Q16:

Determine the perimeter of the triangle whose sides have the same length of 22 cm.

Q17:

What is the range of possible perimeters, , of the given figure if and ?

• A
• B
• C
• D
• E

Q18:

Find the perimeter of a triangle whose side lengths are 7, 25, and 22.

Q19:

Find the perimeter of a triangle whose side lengths are 8 cm, 10 cm, and 4 cm.

Q20:

A triangle of perimeter 37 has two sides of lengths 11 and 8. What is the length of the third side?

Q21:

Calculate the perimeter of the triangle.

Q22:

A triangular fountain has a perimeter of 123 feet. If one of its sides is 32 feet long, and another is 57 feet long, determine the length of its third side.

Q23:

What is the perimeter of triangle , given that , , and ?

Q24:

A triangle has a perimeter of 44. If two of the sides have lengths 19 and 13, what is the length of the third side?

Q25:

Determine the perimeter of the triangle , given that , , and .