Question

The perimeter of a triangle is (17x-3) cm. If its two sides are (2x-5) cam and (7x+4) cm.what is the length of its third side.​

Answer 1

Answer:

The length of the third side is (8x – 2) cm

Step-by-step explanation:

Given :

• The perimeter of a triangle is (17x-3) cm.
• Its two sides are (2x-5) cm and (7x+4) cm

To find :

the length of the third side

Solution :

Let the length of the third side be 'y' cm

The perimeter of a triangle is the sum of the lengths of the three sides.

(2x – 5) + (7x + 4) + y = 17x – 3

2x – 5 + 7x + 4 + y = 17x – 3

9x – 1 + y = 17x – 3

y – 1 = 17x – 9x – 3

y – 1 = 8x – 3

y = 8x – 3 + 1

y = (8x – 2) cm

Therefore, the length of the third side is (8x – 2) cm.

Verification :

Check if the sum of the lengths of the three sides equals the given perimeter of the triangle.

= 2x – 5 + 7x + 4 + 8x – 2

= (2x + 7x + 8x) – 5 + 4 – 2

= (17x – 3) cm

= given perimeter

Hence verified!