<PRE><B>Question 889745</B>
7a + 3s = 1025
3a + 7s = 725
----------------- Add
10a + 10s = 1750
a + s = 175
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7a + 3s = 1025
3a + 7s = 725
----------------- Subtract
4a - 4s = 300
a - s = 75
a + s = 175
2a = 250
a = 125
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