
Andy C. answered 09/13/17
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3y + 2 > 12 - y
3y + 2 - 12 + y > 0 <--- everybody to left side, signs change
4y - 10 > 0 <---- combines like terms
4y > 10 <---- adds 10 to both sides
y > 10/4 = 5/2 <--- divides both sides by 4, then reduces to lowest terms.
CHECK:
Let y=3: 3(3)+2 > 12 - 3 --> 9 + 2 > 12 - 3 ---> 11 > 9 YES it works
Let y=0: 3(0)+2 > 12 - 0 ---> 0 + 2 > 12 - 0 --> 2 > 12 ; Fails as expected
y=5/2 : 3(5/2) + 2 = 15/2 + 2 = 15/2 + 4/2 = 19/2 vs/ 12 - 5/2 = 24/2 - 5/2 = 19/2
y > 5/2 or (5/2, infinity)