<PRE><B>Question 1081896</B>
she pays 20 dollars plus .04 * x where x is the number of minutes she consumed.


if she has been charged 79.36, then take 20 off of that and she has been charged 59.36 for minutes of use.


divide 59.36 by .04 and she has been on the phone for 1484 minutes.


your equation is c = 20 + .04 * x


c is the total cost
x is the number of minutes.


since c is 79.36, the formula becomes 79.36 = 20 + .04 * x
subtract 20 from both sides of the equation to get 59.36 = .-04 * x
divide both sides of the equation by .04 to get 59.36 / .04 = x
solve for x to get x = 59.36 / .04 = 1484 minutes.


1484 * .04 + 20 = 79.36
solution looks good.


let x = m and you get the same solution.


c = 20 + .04 * m
79.36 = 20 + .04 * m
59.36 = .04 * m
m = 59.36 / .04 = 1484



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