Assignment 16

1. You wish to make one liter of a 3% salt solution by mixing a 7%salt solution with a 1% salt solution. How much of each do you need?

2. At the beginning of the year, stock in Alf’s Automotive, Betty’s Boots, and Cathy’s Cameras were each selling for $10 a share. Dave bought a total of $5000 worth. He bought twice as many shares of CC as of BB. At the end of the year, AA was selling for $12, BB for $13, and CC for $9. If Dave’s investments were then worth $5500, how many of each did he buy?

3. Find the equation of the circle ((x-a)² + (y-b)² = r² ) that goes through the points (1, 1), (0, 2), and (3, 2). [Hint: subtract equations.]

4. The height in meters of a ball thrown upward is given by –4.9t² + at + b. If the position is 2 m at t=0, and 5 m at t=1, when does the ball hit the ground?

5. For what value of C does the following system have no solution? Explain.

a. x + y + z = 2, 2x – y + 3z = 6, x – y + Cz = 4