Equation 4x - 9 = 7x + 12 explanation please

x=-7

Step-by-step explanation:

first, subtract 4x from both sides. then you'll get:

-9=3x+12

next subtract 12 from both sides. Then you'll get:

-21=3x

then you divide each side by 3. You get:

x=-7

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.