Question

Subtract the second expression from the first expression:
(1) $4pq-6p^2-2q^2$
(2) $9p^2+2pq-3q^2$.

• A. $15p^2-2pq-q^2$
• B. $-15p^2+2pq+q^2$
• C. $15p^2-2pq-q^2$
• D. $15p^2+2pq+q^2$

Answer 1

The correct option is B $-15p^2+2pq+q^2$

The simplified form of the first expression is $-6p^2+4pq-2q^2$.
The simplified form of the second expession is $9p^2+2pq-3q^2$.
Subtracting the second expression from the first expression, we get,
$=(-6p^2+4pq-2q^2)-(9p^2+2pq-3q^2$)
Rearranging and subtracting the like terms, we get,
$=(-6p^2-9p^2)+(4pq-2pq)+(-2q^2+3q^2)$
$=-15p^2+2pq+q^2$