one issue that throws the whole problem off:
it's --> 19+5=3n
From there --> 3n=24
3n/(3)=24/3
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| n=8 |
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3n-5=19
Add 5 both sides
3n-5+5=19+5
3n=24
Divide by 3 both sides (i.e. Multiply by 1/3 both sides)
3n/(3)=24/3
n=8
19-5=3n
14=3n
14/3= n
4.66 repeating
you would have to ADD 5 to 19 if it's being subtracted from 3n
3n-5=19
+5 +5
3n=24
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3 3
n=8