In this question, you will find the least-squares line, y = Ax + B through the points (0, −4), (1, 4), (4, 5) and (5, 10).

The error (sum of squared errors) is a function of A and B. State this function. (Give an answer in terms of A and B.) E =
Correct: Your answer is correct.

We want to find the values of A and B that minimize this function. As usual, we do this by calculating partial derivatives and then solving the simultaneous equations that result from setting both derivatives equal to zero.

Calculate the partial derivatives. (Give answers in terms of A and B.) ∂E ∂A

Correct: Your answer is correct.

∂E ∂B

Correct: Your answer is correct.

Set both partial derivatives equal to zero. Rearrange the equation ∂E ∂A = 0 to give A in terms of B. A =
Incorrect: Your answer is incorrect.

Now, substitute the above into the equation ∂E ∂B = 0 and solve for B. (Give an exact numerical answer with no variables. Exact answer means give your answer as a fraction or a terminating decimal, DO NOT round.) B =
Incorrect: Your answer is incorrect.

Finally, find the value of A. (Give an exact numerical answer with no variables. Exact answer means give your answer as a fraction or a terminating decimal, DO NOT round.)