Question

The perimeter of a triangle is 69 cm. The longest side is 3 cm less than the sum of the other two sides. Twice the shortest side is 9 cm less than the longest side. Find the length of each side of the triangle.

Answer 1

a =33 longest side

c=24 middle side

b=12 shortest side

1) Gathering the data

2p = 69

a= (b+c)-3

2c= 9 -a

c = (9-a)/2

a+b+c = 69

2) Plugging in the equation a+b+c = 69

(b+c)-3 + b +c = 69

b+c -3 +b+c = 69

2b +2c =72

2(b+c)=72

b+c=36

a = 36 -3

a=33

c=(33-9)/2

c=24/2

c=12

a =33 longest side

c=24 middle side

b=12 shortest side