1. Solving Application Problems Using System of Equations
Section 4.3
Solving Application Problems Using System of Equations

2. Problem solving procedure
1. Select a variable to represent each unknown.
2. Write a system of equations. (# of equations is the # of variables)
3. Solve the system.
4. Answer the question (include units if applicable)

3. Examples, from p
#6 As of June 2008, the US Senate and House of Representatives had a combined payroll of $97 million. If the payroll for the House of Representatives was $57 million more than that of the Senate, how much was allocated to each branch of Congress?

4. #12 The number of people infected with West Nile Virus in the US has been decreasing. In 2003, approximately times as many people were infected as in If a total of 10,586 people were infected during those two years, find the number infected each year.

5. #30 How much of a 45% saline solution and a 30% solution must be mixed to produce 20 liters of a 39% solution?
#32 Marta invested twice as much money in an account paying 7% interest than she did in an account paying 4% interest. If the total interest paid was $720, how much did she invest in each account?