please help!!!!!!!!!!
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[tex]f(x)=2x^2-4x+1[/tex]
Substitute the values of x to the equation of the function f:
[tex]x=-1\to f(-1)=2(-1)^2-4(-1)+1=2(1)+4+1=7\\\\x=2\to f(2)=2(2^2)-4(2)+1=2(4)-8+1=1[/tex]
Therefore we have two points (-1, 7) and (2, 1).
We can calculate the slope of line l.
The formula of a slope:
[tex]m=\dfrac{y_2-y_1}{x_2-x_1}[/tex]
Substitute:
[tex]m=\dfrac{1-7}{2-(-1)}=\dfrac{-6}{3}=-2[/tex]