Question

tow equal sides of a triangle are each 5 meters less than twice the third side if the perimater of the triangle is 55 meters find the length of its sides​

Answer 1

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Given ,

• Two sides of a triangle are equal and are 5 less than twice the third side.
• Perimeter of the triangle is 55 metres

To Find :-

Length of its sides.

Solution :-

Let the third side be x

Twice of x = 2x

Length of two equal sides = (2x - 5)m

Now,

Perimeter = Sum of all three sides.

= (2x - 5) + (2x - 5) + x

According to question ,

(2x - 5) + (2x - 5) + x = 55

=> 5x - 10 = 55

=> 5x = 55 + 10 = 65

=>x = 65/5

= 13

Therefore, x = 13 m

Ist side = (2x - 5)

= 2×13 - 5

= 26 - 5

= 21 m

2nd side = Ist side = 21 m

3rd side = x = 13 m.

Therefore the sides of the triangle are 21m, 21m and 13m respectively.

Verification :-

Perimeter = sum of all sides

=> 55 m = 21m + 21m + 13m

=> 55 m = 42m + 13m

=> 55m = 55m

Since LHS = RHS, Hence Verified.