Genevieve wants to verify that negative x is the simplified expression of one-fifth (5 x minus 20) minus one-half (4 x minus 8). which procedure can genevieve follow to verify this? add one-fifth (5 x minus 20) minus one-half (4 x minus 8) and negative x. put an equal sign between one-fifth (5 x minus 20) minus one-half (4 x minus 8) and one-fifth (5 x minus 20) minus one-half (4 x minus 8) and then solve for x. substitute 5 into the first expression, substitute 4 into the second expression, and evaluate them. substitute 5 into each expression and evaluate them.