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\\ 2 / 20. Use a system of normal equations to nd the line of best least squares t for the data (1.433), (0.3, 1), (1.2.8) and (214.2). Plot the points and the best t. 21. Use a system of normal equations to nd the quadratic of best least squares t for the data (-2.3,4.88), (-0.928), (0.2,0.8), (1.6,1.1) and (33,39). Plot the points and the best t. 22. Use a system of normal equations to nd the best t of the form ax + bsin(x) for the data (-23,-0.9), (1.8,0.4), (-0.5,0.l), (03,-0.1), (1.7,-0.5), (11,05), (3.9,2.l), (4.9,1.9), (63,21). Plot the points and the best t. 23. Suppose We need more data related to the data in problem 20, but we can't rerun the _ experiment that created the data. Use the solution to problem 20 to estimate the value of y ' associated with x = 1.2. 24. Suppose we need more data related to the data in problem 21, but we can't rerun the experiment that created the data. Use the solution to problem 21 to estimate the value of 3/ associated with x = 1.3. 25. Suppose we need more data related to the data in problem 22, but we can't rerun the experiment that created the data. Use the solution to problem 22 to estimate the value of y associated with x = 1.4