Question

Add: $2p^2{q}^2-3pq+4$ and $5+7pq-3p^2{q}^2$

• A. $-p^2{q}^2+4pq+9$
• B. $5p^2{q}^2+5pq+8$
• C. $p^2{q}^2+5pq+9$
• D. $p^2{q}^2+5pq+8$

Answer 1

The correct option is A $-p^2{q}^2+4pq+9$

Given $2p^2{q}^2-3pq+4$ and $5+7pq-3p^2{q}^2$

On adding we get,

$=(2p^2{q}^2-3pq+4)+(5+7pq-3p^2{q}^2)$

$=2p^2{q}^2-3pq+4+5+7pq-3p^2{q}^2$

$=2p^2{q}^2-3p^2{q}^2-3pq+7pq+4+5$

$=-p^2{q}^2+4pq+9$

$\therefore (2p^2{q}^2-3pq+4)+(5+7pq-3p^2{q}^2)=-p^2{q}^2+4pq+9$