Respuesta :

lucic

Answer:

x = 5 cm

Area = 56 cm²

Step-by-step explanation:

The perimeter of the triangle is given as : 21 cm

The two sides given are : 6 cm and 10 cm. The other side has a length of ;

21 - {6+10} = 21 - 16 = 5 cm

This means the value of x is 5 cm

The rectangle will now have its measurements as ;

Length = 7 cm

Width = x + 3 = 5+3 = 8 cm

The area of the rectangle will be :

A = l * w = 7 * 8 = 56 cm