The perimeter of an isosceles triangle is 15 cm and one of its sides is 4 cm less than the other.

The perimeter of an isosceles triangle is 15 cm and one of its sides is 4 cm less than the other. Find the sum of the sides of this triangle

Given:
triangle ABC – isosceles,
P avs = 15 centimeters,
AB = BC,
AC = AB – 4.
Find the lengths of the lateral sides of an isosceles triangle ABC: AB and BC -?
Decision:
Consider a triangle ABC. Let AC = x centimeters, then AB = BC = x + 4 centimeters. We know that the perimeter of triangle ABC is 15 centimeters. Let’s make the equation:
x + x + 4 + x + 4 = 15;
x + x + x = 15 – 8;
x + x + x = 7;
x * (1 + 1 + 1) = 7;
x * 3 = 7;
x = 7: 3;
x = 7/3;
x = 2 1/3 centimeters – speaker side;
2 1/3 + 4 = 6 1/3 centimeters – sides AB = BC.
Answer: 6 1/3 centimeters.