Arectangular field has an area of 1,764 m^2. the width of the field is 13 m more than the length.
what is the perimeter of the field?
a. 121 m
b. 144 m
c. 168 m
d. 170 m

The answer to the above question is letter d which is 170 m. To get the 170 m, kindly check the below solution: 
x^2 + 13x = 1764 so x = -49 and 36, we take 36 as its the positive value. And the other side is 49. Now use 2(l+b) to find perimeter. You get (36+49)*2 = 170