Jay finds a texting plan that costs a flat fee of $15 per month for 100 texts, plus $.25 per text after that. Which cost function represents this scenario if x equals the number of texts exceeding 100 that Jay sends in a month?

A C(x) = 100 + .25x

B C(x) = .25+ 100x

C .C(x) = .25 + 15x

D. C(x) = 15+ .25x

Question

Jay finds a texting plan that costs a flat fee of $15 per month for 100 texts, plus $.25 per text after that. Which cost function represents this scenario if x equals the number of texts exceeding 100 that Jay sends in a month?

A C(x) = 100 + .25x

B C(x) = .25+ 100x

C .C(x) = .25 + 15x

D. C(x) = 15+ .25x

anonymous · Answer

the constant will be $15 per month, so 15 will be the y intercept in the equation.
Every text over 100 adds $0.25 to the total, so C(x)=0.25x+15