Systems of linear equations

Question

The perimeter of a quadrilateral (four sided polygon) is 57 inches. The longest side is four times as long as the shortest side. The other two sides are equally long and are 4 inches longer than the shortest side. Find the length of all four sides.

Answer 1

Let x+2y +z = 57 where x is the longest side and z is the shortest side. So x= 4z and y= z+4. So now using this information 4z + 2( z+4) +z =57. So 7z + 8 = 57 and 7z = 49 giving z=7 x= 28 and y= 11.

Answer 2