4times a number is increased by 15, the answer is the same as when 70 is decreased by the number

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 table shows the webster family’s monthly expenses for the first three months of the year. they are $2,687.44, $2,613.09, and $2,808.64. what is the average monthly expenditure for all expenses?

Assume that 1400 births are randomly selected and 1378 of the births are girls. use subjective judgment to describe the number of girls as significantly high, significantly low, or neither significantly low nor significantly high. choose the correct answer below. a. the number of girls is neither significantly low nor significantly high. b. the number of girls is significantly high. c. the number of girls is significantly low. d. it is impossible to make a judgment with the given information.