1. Solve for X and Y in the following problems. Make sure you show all your work.
a. X + Y=7 , X + 2Y = 11
b. 3X + 7Y = 24, 9X + 5Y = 24
c. 4X + Y = 17, 2X + 3Y = 21
d. 18X + Y = 42, 6X - 3Y = -6
2. Suppose Bob owns 2,000 shares of Company X and 10,000 shares of Company Y. The total value of Bob's holdings of these two companies is $340,000.
Suppose Frank owns 8,000 shares of Company X and 6,000 shares of Company Y. The total value of Franks holdings of these two companies is $340,000.
a. Write equations for Bob and Frank's holdings. Use the variables X and Y to represent the values of shares of Company X and Company Y.
b. Solve for the value of a share of Company X and Company Y. Show your work so you can get partial credit even if your final answer is wrong.
3. Solve for X, Y, and Z in the following systems of three equations:
a. X + Y + 2Z = 5
X + Y = 5
X + 3Y + Z = 11
b. X + 10Y + Z = 52
5X + Y + 4Z = 15
X + 2y - 3Z = 12
c. 22X + 5Y + 7Z = 12
10X + 3Y + 2Z = 5
9X + 2Y + 12Z = 14
1A: X=7-Y, X=11-2Y
1B: 3X=24-7Y, 9X=24-5Y
1C: 4X=17-Y, 2X=21-3Y
1D: 18X=42-Y, 6X=-6+3Y
2: Let X the value of each share of Company X
Let Y the value of each share of ...
This solution shows step-by-step calculations to solve systems of linear equations.