Question

If ` x in N and |[x+3,-2],[-3x,2x]|=8` , then find the value of x.

Answer 1

`|[x+3,-2],[-3x,2x]|=8`

⇒(x+3)2x−(−2)(−3x)=8

⇒2x²+6x−6x=8

⇒2x²=8

⇒x²−4=0

⇒x²=4

⇒x=2 [x ≠ -2 ∵ x ∈ N]