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The multiplication property of zero states that the product of any number and 0 is 0. what must be true about either a or b to make ab=0

An equation representing lyle’s hedge-trimming business is a = 12n - 300 where a is the amount of profit or loss in dollars and n is the number of hedges trimmed. how would the graph of lyle’s business change if the equation a = 10n - 300 represented his business? the graph would be flatter. the graph would be steeper. the graph would start closer to the origin. the graph would start lower on the y-axis.

Given the equation f(x)=a(b)x where the initial value is 40 and the growth rate is 20% what is f(4)