thank you!

The curve below has a horizontal tangent line at the point ( 4, 1) and at one other point. Find the coordinates of the second point where the curve has a horizontal tangent line. 9x + 72x + 25y + 200y = - 319 x-coordinate of second point = y-coordinate of second point = Preview Preview - Find an equation of the tangent line to the graph of x + 3xy + y = 15 at the point (1, 2). y= Preview