Calculate the altitude of a triangle corresponding to its shortest side of it's area is 720cm², perimeter is 180cm and two of its sides are 80cm and 18cm.

altitude = 80 cm

Explanation:
1- getting the third side:
We are given that:
perimeter of the triangle is 180 cm
Two of its sides are 80 cm and 18 cm
This means that:
180 = 80 + 18 + third side
third side = 180 - (80+18)
third side = 82 cm

2- deducing the shortest side that we will use to get the altitude:
We have the three sides of the triangle 80 cm, 18 cm and 82 cm
It is obvious that the shortest side is 18 cm
We will use this side to calculate the altitude since we are given that the altitude corresponds to the shortest side.

3- getting the altitude:
area of triangle = 0.5 * base * altitude
We have:
area of triangle = 720 cm²
base = 18 cm
Substitute to get the altitude as follows:
720 = 0.5 * 18 * altitude
720 = 9*altitude
altitude = 80 cm

Hope this helps :)