Question

Which of the following is equivalent to (2a^2-6ab+4b^2)-(-a^2+2ab-2b^2)

Answer 1

(2a^2-6ab+4b^2)-(-a^2+2ab-2b^2)

=2a^2-6ab+4b^2+a^2-2ab+2b^2

=2a^2+a^2-6ab-2ab+4b^2+2b^2

=3a^2-8ab+6b^2