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Question 176857: Can anyone please help me with this problem?
FInd the value of y:
3x-2y=-7
-7x-3y=-22
Answer by gonzo(654)   (Show Source):
You can put this solution on YOUR website! x = 1
y = 5
here's how:
3x - 2y = -7
-7x - 3y = -22
you want to eliminate either the x or the y so you have one unknown and can solve for that.
if you mutiply the first equation by 7 and you multiply the second equation by 3 you will get:
21x - 14y = -49
-21x - 9y = -66
if you add these 2 equations together, the x will cancel out and you will be left with:
-23y = -115
divide both sides by -23 to get:
y = -115/-23 = 5
since y = 5, substitute in either equation to solve for x.
use 3x - 2y = -7
this becomes:
3x - 2*5 = -7
which becomes:
3x - 10 = -7
which becomes:
3x = 3
which becomes:
x = 1
you have:
x = 1
y = 5
substitute in the other equation to see if these values will hold up.
take:
-7x - 3y = -22
substitute 5 for y and 1 for x:
-7(1) - 3(5) = -22
this becomes:
-7 - 15 = -22
which becomes:
-22 = -22
which means that the value for x and y are good since they solve both equations.
your answer is:
x = 1
y = 5
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