Let x-------------> amount added <span>to each side </span>A-------------> area increased----------> 84 ft²
we know that A=(10+x)*(5+x)=84-----------> 10*5+10*x+5*x+x² 50+15x+x²=84----------> x²+15x-34=0 <span>solving the second order equation </span>x1=-17 x2=2
There are 100 possibilities for the last two digits [ if we include
00].....therefore....you have 1/100 chance [1 % ] chance of
choosing the correct one.....