Question

$(3x - 9 {)}^{2} = 36$
pfv......

Answer 1

(3x-9).(3x-9)=36

9x²-27x-27x+81=36

9x²-54x+81-36=0

9x²-54x+45=0 (÷9)

x²-6x +5=0

∆=(-6)²-4.1.5
∆=36-20
∆=16

x=-(-6)±√16/2.1
x= 6±4/2

x1=6+4/2=10/2=5
x2= 6-4/2=2/2=1

S={5,1}