Isosceles Triangle — Perimeter and Equal Sides Given: The perimeter of an isosceles triangle is 26 cm and the two equal sides together measure 20 cm. Find the third side and each equal side (respectively).

Introduction / Context:
An isosceles triangle has two equal sides. When the perimeter and the sum of the equal sides are known, the third side follows by subtraction. This problem tests reading precision and simple arithmetic within geometric context.

Given Data / Assumptions:

• Perimeter P = 26 cm
• Equal sides together = 20 cm ⇒ each equal side = 10 cm
• Third side = P − (sum of equal sides)

Concept / Approach:
Let the equal sides be a and a; given a + a = 20 ⇒ a = 10. The third side b = P − 2a. Report the ordered pair: third side first, then each equal side, as requested in the stem.

Step-by-Step Solution:

Verification / Alternative check:

Why Other Options Are Wrong:

• Other pairs do not sum to the required perimeter with two equal sides of 10 cm.

Common Pitfalls:

• Reporting the equal side first despite the requested order.

Final Answer:
6 cm and 10 cm.