What is the most efficient first step to isolate the variable term on one side of this equation?
-9x=-4x+5
a) Subtract 5 from both sides.
b) Add 5 to both sides.
c) Subtract 9x from both sides.
d) Add 4x to both sides
-4x and -4x are opposite terms, so they cancel each other out. Once you add 4x to both sides, the variable term (-5x) is isolated on one side of the equation.