what is the r^2 value of y=-35,000+130a+20,000b?

Answer 1

Given what you have here, r-squared represents the percentage of the data explained by the model. If you were given an r^2 of 0.75 for the model above, 75% of the data is explained by the model, the other 25% would be random error.

If ALL the data are ON the line of the curve, r^2 = 1.0, or 100%, since there is no error (points OFF the data), left.