Pls help I’ll brainlest ASAP

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 .

Write the linear inequality shown in the graph. the gray area represents the shaded region. y> -3y+5 y> 3x-5 y< -3x+5 y< 3x-5

Answer this question only if you know the answer! 30 points and