Ответ:

1)(x + 6)2-10x = x(x+3)

x2 + 2×x×6 + 36 = x2 + 3x

x2 + 12x - x2-3x =-36

9x=-36

x=-36÷9

x=-4

2)(x-4)2 =(x+5)2

x2-2×x×4+16=x2+2×x×5+25

x2-8x+16=x2+10x+25

x2-8x-x2+10x=25-16

2x=9

x=9÷2

x=4.5

3)(4x+2)2=4x(4x+8)

4x2+2×4x×2+4=16x2+32x

16x2+16x-16x2-32x=-4

-16x=-4

x=0.25

4)(x+8)2=x2+96

x2+2×x×8=x2+96

x2+16x-x2=96

16x=96

x=96÷16

x=6