Solve for |4x+3| < 9

Under the absolute value could be positive or negative number, but absolute value make them both positive.

For positive number we can write is (4x+3) and for negative - (4x+3)

4x+3<9

4x< 6

x< 3/2 (-∞, 3/2)

- (4x+3) <9

-4x-12<9

-4x<21

x>-21/4 (-21/4, + ∞)

(-∞, 3/2) ∩ (-21/4, + ∞) = (-21/4, 3/2) it could be written as (-5.25, 1.5)