mth122 peer discussion responses 150 words each
Please reply to both POST1: and POST2: I have also included the initial post Initial Post as reference. 150 words each
For this discussion, complete the following tasks:
- Write two linear equations with two variables that model something from your daily life.
- Solve the system of equations in two ways.
- Discuss which method you liked better and why.
- In your responses to peers, contrast your preferences for how to solve systems of equations.
POST1:
Hello Class, and happy final week! Since I had my daughter I like to shop more for her than myself and I have determined a shopping situation suitable for a linear equation.
A store has a sale on baby clothes. I can buy tops for $2.00 per piece and bottoms for $3.00 per piece. I bought a total of 13 pieces for $31.00 (What a deal!).
If tops=x and bottoms=y, my equations will be
(1) x+y=13
(2) 2x+3y=31
Substitution Method:
x+y=13
x=13-y
2(13-y)+3y=31
26-2y+3y=31
26+y=31
y=31-26
y=5
x+5=13
x=13-5
x=8
So x=8 and y=5 so 2(8)+3(5)=31 or 16+15=31
Elimination Method:
2x+3y=31 Multiply by 1 2x+3y=31
– x + y=13 Multiply by 2 – 2x+2y=26
y=5
Then back-substitute 2x+3(5)=31
2x+15=31
2x=31-15
Divide both sides by 2
x=8
So, again x=8 and y=5
I found substitution to be the easier method for me because it was pretty straight-forward, elimination calls for multiplying and having to figure factors in order to determine equal x-coefficients, which means extra work.
Thank You
Jasmine
References:
Bittinger, M. L., Beecher, J. A., Ellengoben, D. J., and Penna, J. (2016). Algebra & trigonometry: Graphs and models (6th ed.). [E-reader version]. Upper Saddle River, NJ: Pearson. Retrieved from http://www.pearsonmylabandmastering.com/northameri…
POST2:
Hello class,
I sell two colors of the same product on Amazon, but they don’t give me exact sales data until a couple days later. So, I have found this system of equations thing to be quite useful.
For instance: today I have sold 32 units for $574. I charge $20 for whites and $17 for blacks.
w+b=32
20w+17b=574
isolate b=32-w
20w+17(32-w)=574
20w+544-17w=574
20w-17w=30
3w=30
w=10
then plug into w+b=32 to find the amount of blacks I have sold today is 22
in interval form would be: (10,22)
to solve by elimination:
20w+17b=574
(w+b=32)-20
——————–
20w+17b=574
-20w-20b=-640
——————–
combine like terms
(-3b=-66)/-3
b=22
w+(22)=32
w=10 — or (10,22)
Personally, I like the synthesis method because its a little easier to convey and follow in writing. They’re both good ways of solving, but for this assignment I’ve found the synthesis to be more preferable.
Cheers,
– Sam