Question 2459: I am still having problems with trying to figure this particular problem. Can you please provide me with some assistance. Thank you very much.
Solve for X and Y
4X + Y = 16, 2X + 3Y = 24
Answer by longjonsilver(2297)   (Show Source):
You can put this solution on YOUR website! 4x + y = 16 --eqn1
2x + 3y = 24 --eqn2 multiply this by 2, to scale it so that the 2 equations have the same number of X's.
4x + y = 16 --eqn1
4x + 6y = 48 --eqn2
The 2 X terms both have the same sign (both positive). SSSSame sign means SSSSubtract, ok? So eqn1 - eqn2 is:
-5y = -32
so y = (-32)/(-5)
--> y = 32/5
Put this answer into either eqn1 or eqn2, it doesn't matter which.
I shall put it into eqn1, because that has smaller amounts of x and y...
4x + 32/5 = 16
4x = 48/5
--> x = 12/5
Now, put both your answers into the other equation and make sure they equal 24, as stated...
2(12/5) + 3(32/5) --> (24+96)/5 --> 120/5 which is 24...correct.
The beauty of checking like this is knowing that your answer is correct. If you find it is wrong, you can go back and look at your working for the error that you know is there!
jon
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