The perimeter of an isosceles triangle is 20 cm. The base of the triangle is 4 cm

The perimeter of an isosceles triangle is 20 cm. The base of the triangle is 4 cm less than its lateral side. Find the base and side of the triangle.

Let’s solve this problem using the equation.

Let the length of the base of an isosceles triangle be x centimeters, then the lengths of its lateral sides are (x + 4) centimeters. We know that the perimeter of this isosceles triangle is 20 centimeters. Let’s make the equation:

x + x + 4 + x + 4 = 20;

x + x + x = 20 – 8;

3 * x = 12 (in order to find an unknown factor, you need to divide the product by a known factor);

x = 12: 3;

x = 4 centimeters – base length;

4 + 4 = 8 centimeters – the length of the sides.

Answer: 4 centimeters; 8 centimeters; 8 centimeters.



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