1.

12⁴/6⁴=( 2⁴ × 6⁴ ) / 6⁴ = 2⁴

2.

1/9 × х² -9=0

х² - 81= 0

х²= 81

х= ±9

х= -9

х=9

х(1) = -9 , х(2)= 9.

3.

2х² - 10х+8=0

х²-5х+4=0

х²-х-4х+4=0

(х-1)× (х-4)= 0

х=1

х=4

х(1)= 1, х(2)= 4.