1

Problem

The perimeter of an isosceles triangle is 15 units. Find out the length of the third side of the triangle if the equal sides measure 4 units each.

2

Step

Given, Perimeter of an isosceles triangle (P):
The length of the equal side is

15 units
4 units

3

Formula

Perimeter of an Isosceles triangle:
Perimeter (P) = 2 × (length of equal side) + length of the third side

4

Step

Substitute the values into the formula

15 = (2 × 4) + c

4

Step

Now, solve for c:

15 = 8 - c
c = 15 - 8
c = 7 units

4

Solution

The length of the third side of the isosceles triangle is 7 units.

5

Sumup

Please summarize Problem, Clue, Hint, Formula, Steps and Solution

Choices

6

Choice-A

This is incorrect because it does not satisfy the perimeter equation 2a + c = 15

Wrong 1 unit

7

Choice-B

This is incorrect because it does not satisfy the perimeter equation 2a + c = 15

Wrong 12 units

8

Choice-C

This is incorrect because it does not satisfy the perimeter equation 2a + c = 15

Wrong 10 units

9

Choice-D

It is correct because it satisfies the given perimeter condition

Correct 7 units

10

Answer

Option

D

11

Sumup

Please summarize choices