Question 171362
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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