I need help thank you

We want this:

3x^2 + 15x - 56 + (x - 8)^2

First, expand (x - 8)^2 using FOIL.

So, (x - 8)^2 = (x - 8)(x - 8).

(x - 8)(x - 8) = x^2 - 16x + 64.

We now add like terms.

3x^2 + 15x - 56 + x^2 - 16x + 64

4x^2 - x + 8

Done.

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.