In the diagram of triangle ADC below, EB II DC , AE=12, ED=15, and BC=8.75. What is the length of AB, to the nearest tenth?

so, converting firstly the mixed fractions to improper fractions and then "adding".

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.