The point P(4,27) lies on the curve y = x+x+7. If Q is the point (x, x+x+7), find the slope of the secant line PQ for the following values of r. If 2 4.1, the slope of PQ is: and if x=4.01, the slope of PQ is: 9. and if x = 3.9, the slope of PQ is: and if x = 3.99, the slope of PQ is: 2. Based on the above results, guess the slope of the tangent line to the curve at P(4, 27).