What is the x value?

sqrt(3-x)+5=9

OK, let's first subtract 5 from both sides

This gives SQRT(3-x) = 4

Now, to get rid of the root, square both sides

We have 3-x = 16

Subtract 3 from both sides

This gives -x = 13

Multiply through by -1

We get x = -13

You should check for yourself that this is correct by putting the answer back into the original problem to make sure it makes sense.

I'll leave that for you........