Question

The perimeter of a triangle is 71 cm. The first side is 3 cm shorter than the second side
The third side is twice as long as the first side.

(a) Form an algebraic equation to represent the information above.

(b) Hence find the longest side of the triangle.​

Answer 1

Answer:

Hence find the longest side of the triangle.

Answer 2

Answer:

Given,

The Perimeter of the Triangle = 71 cm

Let the second side be x

So, first side = (x - 3)

And third side = 2(x - 3)

So,the equation so formed will be,

x + (x - 3) + 2 ( x - 3) = 71 cm

=> x + x - 3 + 2x - 6 = 71 cm

=> 4x = ( 71 + 3 + 6) cn

=> 4x = 80 cm

=> x = 80 /4

=> x = 20 cm

So, the first side = x - 3 = 17 cm

Second side = x = 20 cm

Third side = 2 (x-3) = 2 ( 20 - 3) = 2 x 17 = 34cm

(b) Since 34 is greatest among these three.

=> Hence, the third side is the longest.