d. C = 0.23(m – 100) + 34.99
Let C = X + Y, where
C = Cost of the bill in terms of m
X = First term of the equation
Y = Second term of the equation
X = add additional minutes to $ 0.23 minus the 100 minutes of use allocated.
X = 0.23 (m – 100)
Y = Base price monthly will be $ 34.99
Y = 34.99
C = X + Y
C = 0.23 (m – 100) + 34.99
Note: The only possible answer is 0.23 (m – 100) + 34.99, but we must assume that “m” is greater than or equal to 100, that is, Bill consumes at least his 100 minutes assigned by the base price.
Hope this helps!