Mark Gershon, owner of a musical instrument distributorship, thinks that demand for guitars may be related to the number of television appearances by the popular group Maroon $5$ during th previous month. Gershon has collected the data shown in the following table:

$\backslash$table$[[$Maroon $5$ TV Appearances,$3,5,8,7,8,7],[$Demand for Guitars,$2,5,6,5,9,7]]$

This exercise contains only parts $b,c,$ and $d.$

b$)$ Using the least$-$squares regression method, the equation for forecasting is $($round your responses to four decimal places$)$:

$Y=$