Aphone company offers two monthly plans. plan a costs $18 plus an additional $0.10 for each minute of calls. plan b costs $22 plus an additional $0.08 for each minute of calls.

for what amount of calling do the two plans cost the same?

what is the cost when the two plans cost the same?

true? is that what you're asking or do you mean something else?

1 number

if we use a graphing calculator, there is only one such number that satisfies the conclusion of the mean value theorem, that is, a number such that

where the right-hand side is the average rate of change of f on the interval [0.5,0.75], which is the slope of the secant line.

in the attached graph, the black line is the secant line which has its slope as the average rate of change of f on [0.5,0.75], while the orange line is the only tangent line to the graph of f in the interval that satisfies the mvt conclusion.