Please  help me I dont under stand these. I need help like right now.
How many solutions are there to the following system of equations?

3x – 9y = 0
–x + 3y = –3

A. infinitely many
B.1
C.2
D.0
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What is the solution to the system of equations?
2x + y= -3
x - 2y= -4

(___,___)


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In a recent golf match, Tiger’s score was 4 less than Phil’s score. Their combined scores totaled 140. Let p represent Phil's score and t represent Tiger's score.

Which pair of equations can be used to determine their scores?

A. p – t = 140
p + t = 4

B. p + 140 = t
p = 4

C. p + t = 140
p – t = 4

D. p + t = 140
p + t = 4

(i think this one is C)

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The system of equations is coincident.

What are the missing values?

3x + y= 7
9x + __ y= __

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Allison and her husband Noah both get in their cars and begin to drive at the same time. Allison starts 360 mi from their home and drives directly home at a constant rate of 50 mph. Noah starts at their home and drives away from the home at a constant rate of 40 mph. The system that models this situation is given, where d represents the distance from home, and t represents time, in hours. The solution to the system is (4, 160).

What is the correct interpretation of the solution to this system?

d = 360 - 50t
d =40t

A. Noah will be 160 mi from home and Allison will be 4 mi from home.

B. Allison and Noah will both be 160 mi from home after 4 h.

C. Noah will be 4 mi from home and Allison will be 160 mi from home.

D. Allison and Noah will both be 4 mi from home when they drive for 160 min.

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please help me I dont understand these.