Solve using the multiplication property.

- m = 40

To solve using the multiplication property, we can multiply both sides of the equation by the same value.

In this case, we can multiply both sides of the equation by 1/40 to isolate the variable m.

- m * (1/40) = 40 * (1/40)

This simplifies to:

- m/40 = 1

Now we can multiply both sides of the equation by 40 to solve for m:

- (m/40) * 40 = 1 * 40

This simplifies to:

- m = 40

Therefore, the solution to the equation - m = 40, using the multiplication property, is m = 40.