The perimeter of an isosceles triangle is 48mm. find sides if base is 0.4cm side

Data: Ptr – isosceles triangle perimeter (Ptr = 48 mm); losn (base length) = 0.4lst (side length).

1) Side length: Ptr = lm + 2lst = 0.4lst + 2lst = 2.4lst = 48.

lst = 48 / 2.4 = 20 mm.

2) Base length:

a) losn = 0.4lst = 0.4 * 20 = 8 mm;

b) losn = Ptr – 2lst = 48 – 2 * 20 = 8 mm.

Answer: The side must be 20 mm long; base – 8 mm.