Which expression represents the phrase ''4 times as much as the sum of 15 and 9'' a. 4 x (15+9) b. (4 + 15) x 9 c. 4 + 15 x 9 d. 4 x 15 + 9

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.