Respuesta :
Answer: Option 'C' is correct.
Step-by-step explanation:
Let the fixed monthly charges be x
Let the charges per minutes be y
According to question, we have
[tex]x+500y=\$35\\x+1500y=\$55[/tex]
Now, by using the method of substitution for solving the system of linear equation:
[tex]x=35-500y\\\\\text{ put in second equation i.e.}x+1500y=\$55\\\\35-500y+1500y=55\\\\35+1000y=55\\\\1000y=55-35\\\\1000y=20\\\\x=\frac{20}{1000}\\\\x=\frac{1}{50}[/tex]
Now, put the value of y in x , so we get,
[tex]x=35-500y\\\\x=35-500\times\frac{1}{50}\\\\x=35-10=\$25[/tex]
Hence, the monthly fixed charge is $25
Thus, Option 'C' is correct.
Answer:
C) $25
Step-by-step explanation:
$25 is correct. The slope of the line from (35, 500) to 55, 1500) is 20/1000 = .02, which is her cost per minute. Plug in one of the points into the equation y = mx + b to find b, which is the fixed cost.
Hope this helps
-Amelia
