A curve in the xy-plane is defined by the equation x3+y2−12x+16y=28. Which of the following statements are true? 1. At points where x=−2, the lines tangent to the curve are horizontal.
2. At points where y=−8, the lines tangent to the curve are vertical.
3. The line tangent to the curve at the point (−1,1) has slope 12.