Respuesta :
you would have to use distributive property. it would come out to 3x-9=0 then you would add 9 to -9 and 0. It would then be 3x=9. You would then divide 9 and 3x by 3x. You will get x=3.
if xy=0
assume that at least x or y=0
3(x-3)=0
therefor
3=0 or x-3=0
3=0 is false
therefor
x-3 mus equal zero
x-3=0
add 3 to both sides
x=3
assume that at least x or y=0
3(x-3)=0
therefor
3=0 or x-3=0
3=0 is false
therefor
x-3 mus equal zero
x-3=0
add 3 to both sides
x=3