Question

agora ta certo (x-3)²=16

Answer 1

$(x-3)^2=16\\x^2-6x+9=16\\x^2-6x+9-16=0\\x^2-6x-7=0\\\Delta=b^2-4ac=36+28=64\\x=\frac{-b\pm\sqrt{\Delta}}{2a}\\\\\boxed{x'=\frac{6+8}{2}=7}\\\\\\\boxed{x''=\frac{6-8}{2}=-1}$

obs:

$(x-3)^2=16\\x'=7\\(7-3)^2=16\\4^2=16\\16=16\\\\x''=-1\\(-1-3)^2=16\\(-4)^2=16\\16=16$

Answer 2

( x - 3 )² = 16
( x - 3 ) . ( x - 3 ) = 16
x² - 3x - 3x + 9 = 16
x² - 6x + 9 - 16 = 0
x² - 6x - 7 = 0
a = 1
b = - 6
c = - 7

x = - b±raíz de b² - 4 . a . c / 2 . a

x = -(-6)±raíz de (-6) - 4.1.-7 / 2

x = 6 ± 8 / 2

x1 = 6 + 8 / 2 = 14/2 = 7

x2 = 6 - 8 / 2 = - 2 / 2 = - 1

S = { 7 , - 1 }

Espero ter ajudado !!! :)