The sum of the 9th square number and 3rd cube number is 108
U subtract 4x by 5x and then you add 3 by -21 and the answer is x=18
Answer:
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X/3=2
x=6
x/5=3
x=15
x/7=2
x=14
Each time, you multiply both sides by the denominator.
Hope this helps :)
