#### duffie_stuff

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1. 3x - 4y - 7 = y + 10 x = 10 = 4x - 7y

2. 8x + 24 = 15x + 15y = 80 - 10y

- Thread starter duffie_stuff
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1. 3x - 4y - 7 = y + 10 x = 10 = 4x - 7y

2. 8x + 24 = 15x + 15y = 80 - 10y

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I'm sorry, but I don't understand either of your equations. The first equation has three "equals" signs in it, and the second has two. Each equation should have only one.duffie_stuff said:

1. 3x - 4y - 7 = y + 10 x = 10 = 4x - 7y

2. 8x + 24 = 15x + 15y = 80 - 10y

Please reply with corrections. When you reply, please state the method you are using for solving (matrices? Cramer's Rule? substitution? etc) and show how far you have gotten.

Thank you.

Eliz.

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Okay, but whatduffie_stuff said:i am using elimination and substitution method to solve both of the questions

Does this mean that your two "equations" are actually two different exercises...? So each "equation" should actually be two separate equations, rather than one "equation" with three "equals" signs...?duffie_stuff said:the answer for Q.1 is (-1, 2) and Q.2 is (12, -4)

Please reply with corrections. (Putting the two different equations on separate lines would be helpful.) When you reply, please show what you've tried and how far you've gotten, so we can see where you're needing help.

Thank you.

Eliz.

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i know how to solve Q.2 already.

It is supposed to be like this:

8x + 24 = 15x + 15y -------1

15x + 15y = 80 - 10y-------2

then i use the elimination method. But i still do not know how to solve Q.1.

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And until you tell us what the equations are, we won't know, either.duffie_stuff said:i still do not know how to solve Q.1.

Please reply with corrections. (Putting the two different equations on separate lines would be helpful.) When you reply, please show what you've tried and how far you've gotten, so we can see where you're needing help.

Thank you.

Eliz.

- Joined
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1. 3x - 4y - 7 = y + 10 x = 10 = 4x - 7y