In an equilateral triangle, the side is 7 cm larger than the base, find all sides if the perimeter of the triangle is 38 cm

1) If we designate the length of the lateral side for x cm, then the base, which is less by 7 cm, will be (x – 7) cm.It is known that the triangle is isosceles, then if, according to the condition of the problem, the perimeter is 38 cm, you can write the equation:

x + x + (x – 7) = 38,

3x = 45,

x = 15.

2) Accordingly, the base of the triangle will have a length:

15 – 7 = 8 (cm).

Answer: equal sides are 15 cm long, and the base is 8 cm.