Answer: x = {-2, 2}
Step-by-step explanation:
Tangent means it is touching. Find the intersection of the two equations.
Solve the linear equation for y, then set the two equations equal to each other.
[tex]4y=x+8\qquad \rightarrow \qquad y=\dfrac{x+8}{4}[/tex]
[tex]\dfrac{x-1}{x}=\dfrac{x+8}{4}\\\\\\\text{Cross multiply and solve for x:}\\4(x-1)=x(x+8)\\4x-4=x^2+8x\\.\qquad 0=x^2+4x+4\\.\qquad 0=(x+2)^2\\.\qquad 0=x+2\\.\qquad x=-2[/tex]
To find the next point that is parallel to the linear equation and tangent to the curve, we need to use the linear equation with slope (m) = [tex]\dfrac{1}{4}[/tex] and unknown b.
Let's try b = 0, then the equation of the linear equation is: [tex]y=\dfrac{1}{4}x[/tex]
Set the equations equal to each other and solve for x:
[tex]\dfrac{x-1}{x}=\dfrac{x}{4}\\\\\\4(x-1)=x^2\\4x-4=x^2\\.\qquad 0=x^2-4x+4\\.\qquad 0=(x-2)^2\\.\qquad 0=x-2\\.\qquad x=2[/tex]
This works!!! If it didn't work, we would have tried other values for b until we arrived at a solution.
