Answer:
12+x=24
Step-by-step explanation:
To do this you would just plug in 12 for x to each equation and when you do that the only one that would be right would be 12+x=24
Hi there! Hopefully this helps!
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x + 12 = 30
x = 18.
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15 + x = 15.
x = 0
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x + 5 = 18
x = 13
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