The perimeter of an isosceles obtuse triangle is 45 cm, and one of its sides is 9 cm larger than the other

The perimeter of an isosceles obtuse triangle is 45 cm, and one of its sides is 9 cm larger than the other. Find the sides of this triangle.

Given:
ABC – isosceles obtuse triangle,
АС – base,
AC = AB + 9 centimeters,
the perimeter of the triangle is 45 centimeters,
Find the lengths of the sides of the triangle AB, BC, AC -?
Decision:
Consider an isosceles obtuse triangle ABC. Since it is obtuse, the base of the speaker is larger than the sides. Let AB = BC = x centimeters, then AC = x + 9 centimeters. We know that the perimeter is 45 centimeters. Let’s make the equation:
x + x + x + 9 = 45;
3 * x = 45 – 9;
3 * x = 36
x = 36: 3;
x = 12 centimeters – the lengths of the sides AB and BC.
12 + 9 = 21 centimeters – the length of the base of the speaker.
Answer: 12 centimeters; 12 centimeters and 21 centimeters.