Test 3 – Updated version AName ______

MAT 114

1) Classify the system as consistent or inconsistent, dependent or independent

2x – 5y = −4

10x – 25y = −20

2) Classify the system as consistent or inconsistent, dependent or independent

x + y = −5

x – y =3

3) Solve system of equations by graphing (use the graph provided below)

3x + y = – 9

x + y = –1

4) Solve system of equations using either substitution or elimination method

y = 2x +3

3x + y = −17

5) Solve system of equations using either substitution or elimination method

x − 4y= −5

2x − 4y= −6

6) Solve system of equations using either substitution or elimination method

x + 5y= −2

−3x+6y= 6

7) Solve system of equations using either substitution or elimination method

−4x − 2y= −6

−12x −6y= 18

8) Solve system of 3 equations

x + y + z = 2

x – y + 2z = –2

3x + y + z = –4

9) Solve system of inequalities by graphing (use the graph provided below)

x + 2y ≤ 2

y ≥ –x

Part III: Create system of equations for 3 problems, but you only have to solve 2 of them.

10) How many liters of a 10% alcohol solution and how many liters of a 30% alcohol solution must be mixed together to get 320 liters of a 20% alcohol solution?

11) Mardi received an inheritance of $70,000. She invested part of it at 9% and part at 12%. Her total annual income from the investment was $7200. Find the amount invested at 9% and 12%.

12) The speed of a stream is 5mph. If a boat travels 48 miles downstream in the same time that it takes to travel 24 miles upstream, what is the speed of the boat in still water?

13) A cabin cruiser travels 20 miles in the same time that a power boat travels 40 miles. The cruiser travels 5 mph slower than the power boat. Find the speed of each boat.