The means for the y variable in the two scatterplots shown in Figure 14.34 are both equal to twenty, and the best-fitting lines cross the y axis at the same point and have the same slope.

a. Use the formula for r2 to explain which scatterplot in Figure 14.34 has a larger r2. Do this without actually calculating r2.

b. Which relationship between x and y shown in Figure 14.34 shows a larger proportion of variation in y accounted for by variation in x? Explain how you know.