Answer :
(x+3)(x-3)=16-2x^2
x^2-3x+3x-9=16-2x^2
x^2+2x^2=16+9
3x^2=25
x^2=25/3
x= +/-√25/3
x=+/- 5√1/3
x^2-3x+3x-9=16-2x^2
x^2+2x^2=16+9
3x^2=25
x^2=25/3
x= +/-√25/3
x=+/- 5√1/3