The monthly cost C for a cell phone is $20 each month plus $.10 for each minute used. Write an equation that can be used to find the total cost, in dollars, for a month when m minutes are used.

i think its a and d

step-by-step explanation:

for this case we have by definition, if two lines are perpendicular, then the product of their slopes is -1.

then, given the following line:

so,

we are looking for m_ {2}:

then, the line is given by:

we find "b" replacing the given point:

finally, the equation is:

option c

47.28 or 47.2857143

step-by-step explanation:

you just divide 331 by 7 and you get that answer. ( i think so tho)