Raymond B. answered 04/15/21
Math, microeconomics or criminal justice
3x-2<9 or 3x-2 >-9
3x<11
3x>-7
x < 11/3
x>-7/3
x is in the interval (-7/3, 11/3) or (-2 1/3, 3 2/3)
Try testing that solution with some simple integers in the interval and outside the interval. x= 0, 1<9, x= 4, 12-1>9, x=-3 10>9.
when x=-7/3 or 11/3, 9=9, so use parentheses, not brackets, for the ends of the interval, as the interval does not include the boundaries.
the absolute value signs mean that either 3x-2 <9 or -(3x-2)<9
3x-2<9
x <11/3 is sort of straight forward,
but the 2nd part a little more complex
-(3x-2)<9
-3x +2 <9
-3x <9-2
-3x<7
here's the tricky part, divide by -3, but when you divide (or multiply by a negative number), the direction of the inequality changes direction, so
x>-7/3
which is the same as
-7/3<x
combine that with what you got from the 1st inequality, x<10/3 to get
-7/3<x<11/3, that's the interval of the solution for x, or write as
(-7/3, 11/3) or (-2 1/3, 3 2/3)
Emily V.
i still dont understand04/15/21