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I have been trying to do this problem and I do not know where to start.
What is throwing me off is y/4. I have looked in my textbook and I can not find any example of this problem. I hope someone can help me.
Use elimination to solve: 6x - y/4 = -9 and 3x + 2y = -30
Thank you for the help in advance.
" Use elimination to solve: 6x - y/4 = -9 and 3x + 2y = -30 "
Elimination here means eliminating/removing one of the variables. So if your problem is the y/4, then eliminate the y's. The other y-term is 2y, so you either
>>>make this 2y into y/4 by dividing 2y by 8, or,
>>>make the y/4 into 2y by multiplying the y/4 by 8. It is better this way so that you can avoid too many fractions.
6x -y/4 = -9
Multiply both sides by 8,
48x -2y = -72 -------------(i),
Add that to the other equation, to eliminate the y's,
3x +2y = -30
--------------
51x +0 = -102
x = -102 / 51
x = -2 -----------***
Substitute that into the other equation,
3(-2) +2y = -30
-6 +2y = -30
2y = -30 +6
2y = -24
y = -24/2
y = -12 ------------***
Check those in the 1st equation,
6x -y/4 = -9
6(-2) -(-12)/4 =? -9
-12 +3 =? -9
-9 =? -9
Yes, so, Ok.
Thank you for the help.