geometry help

Question

The perimeter of a triangle is 23.4 cm one side is 6.7 cm long Another is 6.3 What is the length of the third side?

Answer 1

Perimeter of triangle = a+b+c

given a = 6.7,b = 6.3

23.4 = 6.7+6.3+c

c = 23.4-6.7-6.3

c = 23.4-13

c = 10.4

Third side of tringle = 10.4