The perimeter of a square in which a=169cm^2

52 is the perimeter because 13x13=169 and 13+13+13+13=52

2 )      A=a²
       a²=169
        a=√169=13
      P=4a=4 13=52

1. isolate the variable, in this case, d. subtract 35.5 on both sides of the equation.2. 52 subtracted by 35.5 is 16.53. therefore your answer would be d= 16.5this is the basics of pre algebra, isolating variable through adding, subtracting, multiplying, and dividing, if you have any other questions to ask just comment!