Two sides of a triangle are 15 cm and 20cm. The perimeter of the triangle is 50cm. What is the thrid side?

Dear Student!

@nitish06: Very good! Keep posting!

Let the length of third side of the triangle be x cm.

Perimeter of the triangle = 50 cm  (Given)

∴ 15 cm + 20 cm + x cm = 50 cm

⇒ 35 + x = 50

⇒ x = 50 – 35    (Transposing 35 to RHS)

⇒ x = 15

Thus, the length of third side of the triangle is 15 cm.

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