From the text: In algebra courses students are often taught several different forms for linear equations, the slope-intercept form $y=mx+b$, the point-slope form $y-y_1=m(x-x_1)$, and the standard form $ax+by+c=0$. I would like to add a fourth form, the normal form $ax+by+c=0$ with $\sqrt{a^2+b^2}=1$. The rest of this article will use this form and some of the vector algebra that is taught in an upper level pre-calculus course to find the equations of angle bisectors and planes that bisect dihedral angles.