y equals the # of hours u practiced so u substitute y for the # of hours and then solve for x. if im right u multiply x times 7 and u get how many minutes per week u practice the new song. and just the x represents what u practice in a day
210=7(15+x)
210/7=15+x
30-15=x
15 min =x
245=7(15+x)
245/7=15+x
35-15=x
20=x
315=7(15+x)
315/7=15+x
45-15=x
30 min=x
