given

$\displaystyle y=x^2$ and $\displaystyle y=-x^2+6x-5$

I know the derivatives are $\displaystyle 2x$ and $\displaystyle -2x+6 $

how are the equations of 2 tangent lines found to both graphs

the answers are: $\displaystyle y=2x-1$ and $\displaystyle y=4x-4$