Since, Frank needs to save $600 to buy a set of golf clubs. He plans to save $75 per month.
Now, we have to determine the amount of money still he has to save (y) in relation to the number of months (x) in which he has saved money.
Let 'y' be the amount of money he still have to svae.
Let 'x' be the number of months he has saved money.
Total money saved yet = $75 x= $75x
He has to save $600 in total.
So, Money he still have to save = 600 - 75x
So, y=600-75x is the required equation.