slope is how much gained per day
y intercept is at x=0 or when 0 days elapsed or how many canned goods he had when he started
y=-63x+825
this means that he somehow loses 63 cans per day and he started with 825
unless you worded the question wierd and y=how many canned goods he needs to collect, in that case, he started with 0 canned goods, needing to collect 825 total, and collected 63 per day
