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Choose the best answer for the following:

1) Solve by extracting square roots: 2x² = 162.

(a) 9     (b) -9   (c) -9, 9     (d) 81     (e) None of these

2) Solve by any method: x² + 4x - 2 = 0.

  (a) 2 ± sqrt(6)   (b) - 2 ± sqrt( 6)   (c) -2± sqrt(2)     (d)  2 ± sqrt(2) (e) None of these

3) The daily cost in dollars, C, of producing x chairs is given by the quadratic equation

C = x² - 120x + 4200.    How many chairs are produced each day if the daily cost is $600?

(a) 60   (b) 600      (c) 90     (d) 40   (e) None of these

4)  Solve for x:  x² - 2x + 10 = 0.

(a) 7, -1   (b) 1 + 3i, -1 + 3i     (c) 1 + 3i, 1 - 3i

(d) 4, -2       (e) None of these

5) Solve: |x² - 2x| = x.     Hint, use Zoom  to look carefully at the graph to find all the points of intersection

(a) 0     (b) 0, ±1     (c) 0, ±3     (d) 0, 1, 3     (e) None of these

6) Use a graphing utility to solve x² + 4x + 2 < 0.

(a) [-3.41, inf )   (b) (-3.41, -0.59)      (c) (-inf, -3.41] U [-0.59, inf)   (d) (-2, 2)

7) Use a graphing utility to solve x²+ 3x + 9 > 0.

(a) (-inf, -3)U (3, inf)     (b) (-3, 3)    (c) (-inf , inf )   (d) Empty set     (e) None of these

8)  

Determine whether there is positive correlation, negative correlation, or no correlation between the variables.

(a) Positive   (b) Negative       (c) No correlation

9 -10) The table gives the price of a can tuna for the given years. Use the linear regression capabilties of the graphing calculator to find the line of regression and predict the cost for 1999 and 2001. In the table year1 is 1991.

Cost of tuna

Year	price
1	1.69
2	1.66
3	1.64
4	1.54
5	1.39

9)The line of regression written in the form y =  ax + b  is .

10a) The price in 1999 is to the nearest cent .

10b) The price in 2001 is to the nearest cent   .