Step-by-step explanation:
Okay so there are 2 ways to solve this,
1. Simplify the equation to the furthes of your abilities, then substitude 15 instead of n!
2. Substitute 15 instead of n and then solve.
Answer: Solving for just n, will give us, 5 and -5..
However if you plug in 15 instead of n, it will be all real numbers... *1110=135* Which makes totally no sense! Hope this helped.