Lin’s father is paying $20 for a meal. He has a 15%-off coupon for the meal. After the discount, a 7% sales tax is applied. What is the amount of the sales tax for this meal?

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step-by-step explanation:

9 x 8 divided by (5-3)=36

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.