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

Ainfinitely 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?

Ap – t = 140

p + t = 4

Bp + 140 = t

p = 4

C. p + t = 140

p – t = 4

Dp + 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

ANoah will be 160 mi from home and Allison will be 4 mi from home.

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

CNoah will be 4 mi from home and Allison will be 160 mi from home.

DAllison 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.