Elimination was used to solve a system of equations.
One of the intermediate steps led to the equation 9x = 27
Which of the following systems could have led to this equation?
10x - y = 15
x + y =
– 12
9x + 2y = 21
– 9x – 2y = 21
7x – 2y = 15
x + y = 6
< + 3) =
2
-ON - 3
=
3

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.