SOLUTION: When trying to decide if an ordered pair is a solution of a system of liner equation if the x is already negative and the x value given is also negative would it turn positive or s

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Question 171362: When trying to decide if an ordered pair is a solution of a system of liner equation if the x is already negative and the x value given is also negative would it turn positive or stay negative?
Ex: (-9,5)
-x + 3y = 24
Found 3 solutions by stanbon, jim_thompson5910, gonzo:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
When trying to decide if an ordered pair is a solution of a system of liner equation if the x is already negative and the x value given is also negative would it turn positive or stay negative?
Ex: (-9,5)
-x + 3y = 24
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Comment: the negative of a negative is a positive.
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Just substitute the values and see if you get a true statement.
-(-9) + 3(5) = 24
9 + 15 = 24
24= 24
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True so (-9,5) is one (of an infinite number) of solutions.
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Cheers,
Stan H.

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Since we have the ordered pair (-9,5), this means that we're testing the equation using the values x=-9 and y=5


-x+%2B+3y+=+24 Start with the given equation


-%28-9%29+%2B+3%285%29+=+24 Plug in x=-9 and y=5


9+%2B+3%285%29+=+24 Rewrite -%28-9%29 as 9


9+%2B+15+=+24 Multiply


24+=+24 Add. Since the equation is true, this verifies that (-9,5) is a solution of the equation -x+%2B+3y+=+24

Answer by gonzo(654) About Me  (Show Source):
You can put this solution on YOUR website!
ordered pair: (-9,5)
equation: -x + 3y = 24
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you substitute -9 for x and 5 for y
-x + 3y = 24 becomes:
-(-9) + 3(5) = 24
this becomes:
9 + 15 = 24
24 = 24
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the -x in the equation is - (x)
you are substituting for x, not -x
it becomes - (-9)
which then becomes + because a minus of a minus is a plus.
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