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Simplify the expression. -2/5(10+15m-20n)

Create a question with this scenario you could ask that could be answered only by graphing or using logarithm. david estimated he had about 20 fish in his pond. a year later, there were about 1.5 times as many fish. the year after that, the number of fish increased by a factor of 1.5 again. the number of fish is modeled by f(x)=20(1.5)^x.

3x + 4y = 5 x- 3y = -7 solve by substitution