Question

find the length of the third side of a triangle whose two sides are 4cm 5cm and the perimeter is 18cm

Answer 1

hey friend
here is ur answer
HOPE IT HELPS

let the third side be x

perimeter =4+5+x
x=18-4-5=9 cm

Answer 2

Let third side be x
Perimeter of triangle = sum of all side
18 = 4+5+ x
x = 18-9= 9
third side will be 9cm