2.
rock can read 10 books in 30 minutes. how long does it take
rock to read 15 books, if the speed is consistent?

The answer is 45 minutes.

Step-by-step explanation:

30 divided by 10 is 3. So it's 3 minutes per book. 3 multiplied by 15 is 45.

step-by-step explanation:

x = -3

y = -18

step-by-step explanation:

to solve by substitution, substitute one variable and solve for the other. then substitute again to find the remaining variable.

x-1/3(3x-9) = -3 since y=3x-9 substittute y.

x-1/3(3x-9)=-3

x + x +3 = -3

2x+3=-3

2x+3-3= -3-3

2x=-6

x=-3

substitute again into y=3x-9

y=3(-3)-9

y=-9-9

y=-18