Answer:
-4
Step-by-step explanation:
4x+3y=-1
3x + y=-7
Solve for Y
3x+y=-7
-3x. -3x
y= -3x - 7
Plug in Y into the top equation
4x + 3 (-3x - 7) = -1
Distribute the Parenthesis
4x -9x-21=-1
Combine Like terms
-5x = 20
Divide by -5 on both sides
20/-5
x = -4
Answer: 
Step-by-step explanation:

18/30=?/100
18 times 100 = 1800
1800 divided by 30
60%
I'm not 100% sure if I am right, but for number 9 you would pick two points on , let's just say you pick points (0, 1) and (2, -2). Then you would find those points in the table. So in this case the answer would be D. And I'm not really sure how to explain #10 but you basically work out each problem with the graph to see if it makes sense. For example if you try working out problem F it wouldn't make sense since you start of with 10 dollars and earn 2 each day. But on the graph it shows that you are loosing two. Sorry if I didn't explain it right, if you have more questions let me know!