Question

find the value of x if : pqx=(3p+q)^2 - (3p-q)^2

Answer 1

You can use the identity a^2-b^2= (a+b)(a-b)
Here a=(3p+q) and b=(3p-q)
On solving you will get
x=6+6(q/p)

Hope it helps :)

Answer 2

pqx=(3p+q)^2-(3p-q)^2. divided both side by pq . x={(3p+q)^2-(3p-q)^2}/pq. (3p+q)^2=9p^2+6pq+q^2. (3p-q)^2=9p^2-6pq+q^2. x={9p^2+6pq+q^2-(9p^2-6pq+q^2)}/pq. =12pq/pq= 12