College Alge
a
Math XXXXXXXXXXExam 4 Spring XXXXXXXXXXName:________________________
Due: Wed. April 21 at at 11:59 pm Late submissions will not be accepted! The exam must be
submitted through the Vancko Hall assignment tool in jpeg, pdf or word format. SHOW ALL WORK.
ANSWERS WITHOUT WORK RECEIVE NO CREDIT. DO YOUR OWN WORK PLEASE!!
Please box in or circle all final answers.
1. (10 points each) Put each equation into y = mx + b form. Without graphing or trying to solve
the system of equations, state whether the system of equations is consistent, inconsistent, or
dependent. Also indicate whether the system has exactly one solution, no solution, or an infinite
number of solutions. Clearly show your work and your reasoning.
a.
yx
yx
8246
1243
−=
=+
.
456
732
=+
=−
xy
yx
2. (worth 10 pts) Solve by graphing. If you do not use the graphing method, you will receive zero
credit. Clearly indicate the x and y coordinates of the solution on the graph! If you did not
print out the test to complete it, you still have to use the graphing method. Use graph paper, or
use the “virtual online graph paper” found under week of April 5 – 9 on Vancko Hall. Take a
picture of graph and include in exam
submission.
9
1223
=−
=+
yx
yx
3. (worth 10 pts) Solve using the addition method. If you do not use the addition method, you
will receive zero credit.
a)
25710
1424
−=+−
=−−
yx
yx
)
1659
1673
=+−
−=+−
yx
yx
4. (worth 20 pts) Tickets to a show at a theater were sold at $15 each for adults and $9 each for
kids. If 240 tickets were sold for a total of $3060, how many adult tickets and how many kids
tickets were sold? Clearly show work please. Use the alge
aic techniques demonstrated in
class.
5. (worth 10 points) A boat travels with the cu
ent at 22km/h and travels against the cu
ent at
12km/h. What is the speed of the boat in still water? What is the speed of the cu
ent? Clearly
show work. Use the alge
aic techniques demonstrated in class.
6. (worth 20 pts) A chemist wishes to create a 15% sulfuric acid solution. She needs to mix a 10%
sulfuric acid solution with a 30% sulfuric acid solution to obtain 10 liters of a 15% sulfuric acid
solution. How many liters of the 10% solution and how many liters of the 30% solution will she
need to mix? Clearly show work please. Use the alge
aic techniques demonstrated in class.
Report your answers to one decimal place.
BONUS: 5 points All or nothing (which means no partial credit).
Write a system of equations that has the solution (−47,13)