Help~ Don't remember what the point of tengency is.

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The discussion focuses on finding the slope of a tangent line to the function f(x) = x^3 - 18x^2 + 105x - 146 at a point to the right of x = 7, while passing through the point (2, 0). The tangent line can be expressed as y = m(x - 2), where m represents the slope. To find the point of tangency, the conditions that the line must satisfy at x1 include matching the function value and the derivative at that point. The equations m(x1 - 2) = f(x1) and m = f'(x1) lead to a system that can be solved for m and x1. Ultimately, the goal is to determine the appropriate slope and point of tangency for the given function.
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Here is the problem.

f(x)=x^3-18x^2=105x-146 and 2 is a real zero.

now, through the point (2,0), draw a line that is tangent to the graph at a point to the right of the low point at x=7. find the slope of the tangent line using x=2 and the point of tangency.

and here is the graph.
 

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baby garfield said:
f(x)=x^3-18x^2=105x-146 and 2 is a real zero.
I assume that is f(x)= x3- 18x2+ 105 x- 146.
You want to find a line that passes through (2, 0) and is tangent to the graph at some (x,y) where x> 7.

Okay: any line through (2, 0) can be written as y= m(x-2) where m is the slope.

If the line is tangent to the graph at, say x1 , then it must satisfy the equation at that point: we must have m(x1- 2)= x13- 18x12+ 105 x1- 146.
It also must have the same slope there so m= f '(x1)= 3x12- 36x1+ 105.

Solve those two equations for m and x1.
 
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