Question 1203161
The total number of known moons around Saturn, Uranus, and Neptune is 43. The total number of moons around Saturn and Neptune is 9 more than the number of moons around Uranus. Saturn has 2 moons more than twice the number of moons around Neptune. Find the number of moons each planet has.
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S + U + N = 43
S + N = U + 9
S = 2N + 2
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Sub for S:
2N+2 + U + N = 43 ---> 3N + U = 41
2N+2 + N = U+9 ------> 3N - U = 7
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3N + U = 41
3N - U = 7
-------------------------  Add
6N = 48
N = 8
Etc.