2.

2)

(х-8)²-(х-1)²=56

(х-8+х-1)(х-8-х+1)=56

(2х-9)(-7)=56

-14х+63=56

-14х=56-63

-14х= -7

х= -7:(-14)

х= 1/2

3)

(2х-3)²+(4х-1)(4х+1)=5х(4х-11)

(4х²-12х+9)+(16х²-1)=20х²-55х

4х²-12х+9+16х²-1=20х²-55х

20х²-12х+8=20х²-55х

20х²-20х²-12х+55х= -8

43х= -8

х= -8:43

х= -8/43