Byron S. answered • 10/20/14
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You can solve inequalities just like regular equations, with one exception. If you need to multiply or divide both sides by a negative number, then you reverse the direction of the inequality.
-2x + 3 > 11 Subtract 3 from both sides
-2x > 8 Divide by -2, reverse the inequality
x < -4
A graph of this would have an open circle on -4, and an arrow pointing to the left, where the numbers are less than -4.
The second inequality doesn't have negatives, so you can solve exactly like an equation.
Greg C.
-2x + 3 > 11 Add -2x to both sides
3 > 11 + 2x Subtract 11 from both sides
-8 > 2x Divide both sides by 2
-4 > x which is the same as x < -4
Similarly for the second inequality, whether done "with negatives" or not. Of course, subtracting 9 from both sides is easier that subtracting 17 from both side and then subtracting p from both sides, and then dividing by -1, noting that p is already positive and the only other term on the left hand side is 9, so Heavan please consider which terms to do first even though the answer is supposed to be the same in either case.
- Greg, located nearby to Lawrence
10/20/14