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Example of inequality problem solving 1
Question:
For what integer value of x is 2x + 3 > 19 and 3x - 1 < 29 ?
Solution:
In first inequality:
2x + 3 > 19
2x > -3 + 19
2x > 16
x > 8
In second inequality:
3x - 1 < 29
3x < +1 + 29
3x < 30
x < 10
so 8 < x < 10
so the solution is: x = 9

How to solve a one degree inequality? To solve a one degree inequality, the first step is to keep the variable in the left side of the inequality and move the numbers into the right side of the inequality. When move an item cross the inequality, the item will change its sign. This is equivalent to add an item in both side of the inequality. Divide by the coefficient of the variable in both side of the inequality to get the range of the variable. Note: when only multiply (-1) in both side of the inequality, the inequality will change its direction.