Do the opposite of PEMDAS, first subtract 7 from both sides
w (-7) = -√g + 7 (-7)
w - 7 = -√g
multiply -1 (as -√g is the same as -1√g) to both sides
-1(w - 7) = √g -1w + 7 = √g
to get rid of the square root, you must square both sides Note: -1w is the same as -w Note: you are squaring all the terms on the other side, not just one.
(-w + 7)² = (√g)² g = (-w + 7)² g = (-w + 7)(-w + 7) (note, this can be the answer your teacher wants, or g = (-w + 7)² )
Use the FOIL method (First, Outside, Inside, Last)