There was a boy and he had three friends what is a multiplication sentence to find the total

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 .

The interior angles formed by the side of a hexagon have measures of them up to 720° what is the measure of angle a

Rewrite 9 log, x2 in a form that does not use exponents. 9log, x = log, x