SOLUTION: 3- absolute value of 2x+4 greater than or equal to 1

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Question 13510: 3- absolute value of 2x+4 greater than or equal to 1
Answer by rahman(247) About Me  (Show Source):
You can put this solution on YOUR website!
3-abs%282x%2B4%29%3E=1
abs%282x%2B4%29 =
(i) 2x + 4; where 2x%2B4%3E=0 or x%3E=-2
(ii) -(2x+4); where 2x%2B4%3C0 or x%3C-2
Case (i):
3-%282x%2B4%29%3E=1; where x%3E=-2
3-2x-4%3E=1
-2x%3E=1%2B4-3
-2x%3E=2
%28-2x%29%2F%28-2%29%3C=2%2F%28-2%29
x%3C=-1
Solution for this case is -2%3C=x%3C=-1
Case (ii):
3-%28-%282x%2B4%29%29%3E=1; where x%3C-2
3%2B%282x%2B4%29%3E=1
3%2B2x%2B4%3E=1
2x%2B4%2B3%3E=1
2x%2B7%3E=1
2x%3E=1-7
2x%3E=-6
2x%2F2%3E=-6%2F2
x%3E=-3
Solution for this case is -3%3C=x%3C-2
Combine case (i) and (ii), so:-3%3C=x%3C=-1
OK