Question 773437
here are two shepherds talking amongst themselves.
 One says to the other, "Give me one of your sheep so that I may have twice as many as you,",
a + 1 = 2(b-1)
a + 1 = 2b - 2
a - 2b = -3
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 but the other shepherd replies, "No, how about you give me one sheep so that we may have the same number of sheep."
a - 1 = b + 1
a - b = 2
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 How many sheep did each shepherd have?
a - b = 2
a -2b = -3
----------------Subtraction eliminates a, find b
b = 5  sheep
then
a - 5 = 2
a = 7 sheep 
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