solving decimal equations by elimation

Adam1

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Hello I need help with a particular problem. I am stuck on my online homework question which asks to solve the system with coordinates of solutions rounded to second decimal place this problem has taken me all day to solve.Any help would be deeply appreciated, cheers!

The problem presented:

Y= -3.59x + 6.42
Y= 1.23x - 7.32
 
I am trying to solve this problem as it is the last part of my homework before I move into my final two homework assignments. The problem asks to find x and y coordinates by using elimination instead of substitution the main caveat thought is that it asks you to round to the second decimal places so far it has been very trying to solve it. I am due to take final exams and have homework due by this Monday so it is very important if anyone on these forums can help me with the solution.Thank you though.
By the way, the problem presented in the first post is the way it was presented in the homework assignment.
 
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The problem asks to find x and y coordinates by using elimination

Hi Adam:

You should always provide the instructions, when you first post the exercise. (See the forum guidelines summary HERE.)

You already know that the elimination method adds or subtracts a multiple of one equation from the other, in order to eliminate one of the variables, correct? Well, the left-hand side of each equation is the same, so if you simply subtract one equation from the other, the variable y will be eliminated. Solve the resulting equation for x.

Don't worry about rounding, until after you have the values for x and y.

Please show your work.

Cheers :)

PS: As this is on-line homework, how do they determine what method you use?
 
The lecturer doing the example would suggest you do either elimination or substitution, for the problem and thank you for helping me with this algebra problem,best.BTW I just found out that the site I go to do my assignments is undergoing system maintenance so I will post when it is to be finished around 1PM EST.I'll have the assignment posted or screenshot for viewing alongside my attempts.
 
The lecturer doing the example would suggest you do either elimination or substitution, for the problem


Okay, but you already told us that the problem asks you to find x and y "by using elimination instead of substitution".


Asking you use to elimination is not the same as suggesting that you use elimination.

If all you're submitting is the answer, then the machine has no way to determine how you obtained it. In this case, you can solve the problem any way you like, yes?
 
The issue I am having however is that with the problem in my homework assignment I keep getting the incorrect coordinates or I get caught up with the integers and decimal rounding . I will try to copy it word for word to give you a better understanding of the problem thank you for your replies,and a step by step explanation would help me greatly. thanks again.


Here goes nothing:
Use elimination to solve the system with coordinates of solutions rounded to the second decimal place.Verify your work by using "intersect" on a graphing calculator.

The problem being presented:
y=-2.59X +7.01
y=1.05X-6.98

Also to note:I have to simplify my answer, type it in the form of an ordered pair,and round to two decimal places as needed.
 
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Why don't you solve the equation that Denis proposed to you?

-3.59x + 6.42 = 1.23x - 7.32

Calculate x from above.

Then calculate y from one of the given equations (e.g. y = -3.59x + 6.42) using the 'x' found above.

You got your ordered pair.

Following the instructions above - please share your work with us (or tell us exactly where - which line/which word - you are stuck).
 
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I keep getting the incorrect coordinates

Please show your work, so that we can see how you obtained your answer.


I get caught up with the integers and decimal rounding

I don't see any Integers. Please show your work.

Also, can you explain the rounding issue in greater detail? If you need a lesson on how to round decimal numbers, we can help you find one; otherwise, I'm not sure what you're saying.

Here's a simple example of the elimination method, used to solve a system of two equations that's ready-made for eliminating one of the variables (just like in your exercise).

Code:
[FONT=courier new]
Subtract the second equation from the first.

    y = 5.50x + 2.25
 -  y = 1.25x - 1
   -------------------
    0 = 4.25x + 3.25

In the resulting equation, the variable y has been eliminated.

0 = 4.25x + 3.25

Solving this equation shows that x is about -0.7647

To calculate y, we substitute -0.7647 for x in either of the given equations.

y = 1.25(-0.7647) - 1

y = -1.9559

Rounded to two places, the ordered pair is (-0.76, -1.96)

[/FONT]

Cheers :cool:
 
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