1

Problem

An isosceles triangle has a base of length 6 cm, and the two equal sides are each 5 cm long. What is the perimeter of the triangle?

2

Formula

Perimeter of a isosceles triangle is P = 2a + b.

3

Hint

In this triangle the two sides are equal, so here 5cm is the two sides of an isosceles triangle.

4

Step

The base length of a triangle with two equal sides is

5 cm

5

Step

The base length of a triangle sides is

6 cm

6

Step

Substitute the values

P = 2(5) + 6

7

Step

After simplification

P = 10 + 6

8

Step

Simplification

16

9

Solution

Then the perimeter of an isosceles triangle is 16 cm.

10

Sumup

Please summarize steps

Choices

11

Choice-A

This is not correct because it seems to have added the lengths of all sides instead of just the two equal sides and the base

Wrong 20 cm

12

Choice-B

This is the correct answer for the perimeter of the isosceles triangle

Correct 16 cm

13

Choice-C

This is not correct because it seems to have added the lengths of all sides instead of just the two equal sides and the base

Wrong 22 cm

14

Choice-D

This is not correct because it seems to have added the lengths of all sides instead of just the two equal sides and the base

Wrong 24 cm

15

Answer

Option

B

16

Sumup

Please summarize choices