Proof: Radius is Perpendicular to Tangent of a Circle | Geometry

We prove the well known, and very useful, result that the radius of a circle is perpendicular to the tangent that intersects it at a single point on the circle. To do this, we use a really neat contradiction argument, producing a point on our tangent line that will cause some serious trouble! #Geometry How could you prove the converse? That if a radius meets a line at a point on a circle at a right angle, then the line is a tangent? ★DONATE★ ◆ Support Wrath of Math on Patreon for early access to new videos and other exclusive benefits:   / wrathofmathlessons   ◆ Donate on PayPal: https://www.paypal.me/wrathofmath Thanks to Robert Rennie, Barbara Sharrock, and Rolf Waefler for their generous support on Patreon! Thanks to Crayon Angel, my favorite musician in the world, who upon my request gave me permission to use his music in my math lessons: https://crayonangel.bandcamp.com/ Follow Wrath of Math on... ● Instagram:   / wrathofmathedu   ● Facebook:   / wrathofmath   ● Twitter:   / wrathofmathedu   My Music Channel:    / @emery3050