The length of two side of a square is equals to 196 cm find x

Iam trying to solve a linear equation for the shoe size of someone 84" tall taking into consideration example 1 is 69" tall with a shoe size of 9 and example 2 is 72 inches tall with a shoe size of 11. i understand that the equation should be y=mx+b and that on the graph the answer is (3,2) but i just don't understand how to create the equation to solve for 84-inches and 60-inches tall questions. after two days, i need .

What is the solution to the equation below? 3/x-2+6=square root x-2 +8

M.xyz =radians. covert this radian measure to its equivalent measure in degrees.