(х-3)(4х-3)+(2х-1)(2х+1)
___________________  = 1
 (2х+1)(4х-3)

4х² -3х -12х +9 +4х²-1 =  (2х+1)(4х-3)
8х² - 15х +8 = 8х² -6х +4х -3
8х² -15х +8 = 8х² -2х -3
8х² -15х +8 - 8х² +2х +3 = 0
-13х +11 = 0
-13х= -11
х = 11/13