In triangle ABC, sides AB and Ac are equal and have a length of 28mm. What is the length of side BC

In triangle ABC, sides AB and Ac are equal and have a length of 28mm. What is the length of side BC if the perimeter of the triangle is 72mm?

triangle abc
sides AB = 28 mm
ac = 28 mm
ab = ac = 72
the perimeter of the triangle is 72 mm
find the side of BC,
we find the total sum of the two sides, for this we add the first side ab = 28 mm and the second side ac = 28 mm, then we get
28 mm + 2 8 mm = 5 6 mm is the sum of the two sides AB and AC
according to the triangle rule, the sum of all sides is equal to the perimeter,
that is, side ab + side ac + side sun = perimeter
that is, side AB + side AC + side Sun = 72 mm
56 mm + side h = 72 mm
72 – 56 = 16 mm – this is the side of the BC
Answer: 16mm