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sarahlikewoe
2. Forrest Lumber uses the function S(t) = -105t + 840 to determine the salvage value S(t), in dollars, of a table saw t years after its purchase. How long will it take the saw to depreciate completely? 9 years 10 years 8 years 7 years
you could simply use trial and error as you only have four options, for example replace t with 9 and see if it equals 0 if the number is below 0 you need less time, if above try with a higher number