This will be your opportunity to be the teacher. Click on “View Full Description and attachments” below for the directions and questions. Be sure to open the file that says “MATH110 Read This First” before you jump in!

Read the attached files. First read the one entitled “MATH110 Read this first,” and then open the file called “Systems of Equations Problems with Answers.”

Pick ONE of the problems that has not already been solved, and demonstrate its solution using either the substitution or elimination method.

The answers are at the end of the file, so don’t just give an answer—we can already see what the answers are. Don’t post an explanation unless your answer matches the correct one!

For this forum, be sure to do the following in addition to reading the full description and the attachments from the forums main page:

-In the subject line, put the question number and a brief description of the question.

-Copy the problem statement into the body of the posting.

-Define your variables.

-Write two equations based on the question.

-State the method you are using and solve the system of equations.

-Answer the question in a complete sentence.

You do not need to response to classmates’ posts for this forum.

System of Equations Sample Post

At a dog park, there were a total of 18 dogs and people combined.  There were a total of 50 legs on the dogs and people.  How many dogs and people were at the park?

Let d = number of dogs at the park; then 4d = total number of legs on the dogs.

Let p = number of people at the park; then 2p = total number of legs on the people.

Equation 1:  The total number of dogs and people at the park is 18:  d + p = 18

Equation 2:  The total number of legs at the park is 50:  4d + 2p = 50

Use substitution to solve the system of equations.

Solve Equation 1 for p by subtracting d from each side:  p = 18 – d

Substitute 18 – d for p in Equation 2 and then solve for d:

                4d + 2(18 – d) = 50

                4d + 36 – 2d = 50               distribute on the left side

                2d + 36 = 50                        combine like terms on the left side

                2d = 14                                  subtract 36 from each side

                d = 7                                      divide both sides by 2

If d = 7, then p = 18 – 7 = 11. 

Check number of legs:  4(7) + 2(11) = 28 + 22 = 50.

So there were seven dogs and eleven people at the park.