Solve each system by substitution. 1) 2x - 6y = 18
x + 3y = -21

2)y = 2x + 7
2x - y = -3

3) -5x + 6y = -9
3x - 4y = 5

4) -x + 7y = 10
y = 5x - 18

5) y = 4x + 8
y = 5x + 10

6) x + 5y = -7
-5x - 4y = 14

7) -21x + 12y = -9
7x - 4y =3

8) y = -4x - 23
y = 4x + 9

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. create a question you could ask that could be answered only by graphing or using a logarithm.

Me i'm timed ! a. -2 to 1 b. -1.5 to 0.5c. 0 to 1d. 0.5 to 1.5

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