Well for a rectangle, the area
A=Length x Width,
1764=Length x Width,
Since the width of the field is 13 m more than the length, the length will be equal to the with + 13,
L=W+13,
1764=LW
1764=(W+13)(W)
W=36 meters
They want the perimeters, so add them up
2W+2L
=2(36)+2(49)
=170 meters
