The base of an isosceles triangle is 4 cm less than the side, the perimeter of the triangle is 20 cm

The base of an isosceles triangle is 4 cm less than the side, the perimeter of the triangle is 20 cm, find the sides of the triangle.

Given:

a =? cm ;

b =? cm ;

c = 4 cm less than the side;

P = 20 cm.

In an isosceles triangle, the sides are equal.

The perimeter of an isosceles triangle is calculated by the formula: P = a + b + c.

Let’s take for x (cm) – the base of an isosceles triangle:

1) 2 (x + 4) + x = 20;
3x + 8 = 20;
x = 4 (cm).

Therefore, the lateral sides of an isosceles triangle are:
2) x + 4 = 8 (cm).

Answer: 4 cm. The base of the triangle, 8 cm. The sides of the isosceles triangle.