Home » Blog » Sum of negatives is negative.

Sum of negatives is negative.

Prove that the sum of two negative numbers is negative.


Proof. Let x,y be negative numbers, i.e., x < 0 and y < 0. By Theorem I.25, x+y < 0 + 0 = 0. Thus, x+y is negative as well. \qquad \blacksquare.

Point out an error, ask a question, offer an alternative solution (to use Latex type [latexpage] at the top of your comment):