Tangent line parallel to another line At what point of the parabola $y=x^2-3x-5$ is the tangent line parallel to $3x-y=2$? Find its equation.
I don't know what the slope of the tangent line will be. Is it the negative reciprocal? 

Slope of  tangent to parabola $y=x^2-3x-5$ is parallel to slope of line $3x-y=2$ when the angle between them is $0$.
Given parabola
$$y=x^2-3x-5$$
Differentiating w.r.t. "x"
$$\frac{dy}{dx}=2x-3$$
Slope of tangent to parabola
$$m_1=\frac{dy}{dx}=2x-3$$
Given line
$$3x-y=2$$
Just to write in the form of $y=mx+c$
$$y=3x-2$$
So the slope of line is
$$m_2=3$$
Now to find the angle between two slope we have
$$tan\theta = \frac{m_2-m_1}{1+m_2m_1}$$
$$tan\theta = \frac{3-2x+3}{1+3(2x-3)}$$
Here we need to find the value of "$x$"
