9(x-3)²=729

9(x-3)²=729
9(x-3)²=729

9(x-3)²=729
(x-3)²=81
(x-3)²=9²
∴x-3=9 x-3=-9
∴x=12 x=-6

(x-3)²=81
x²-6x+9-81=0
x²-6x-72=0
(x-12)(x+6)=0
∴x=12 x=-6

（x-3)²=81→x-3=根号81→x-3=9→x=9+3→x=12

(X-3)²=81
x-3=9
x=12