(HELP) ples help me with 1, 2, 3

Okay so number 3 is either undefined or Zero. I always forget which is which.

Step-by-step explanation:

But for 1 and 2 use your solution m=rise/run. Or you could count the ways down, like say, for number 1 it runs over 3 from a point and goes up till the next point. I hope this helps.

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