Answer:
10
Step-by-step explanation:
[tex]n-number\\\\\dfrac{1}{5}n+5n=7n-18\qquad\text{multiply both sides by 5}\\\\5\!\!\!\!\diagup^1\cdot\dfrac{1}{5\!\!\!\!\diagup_1}n+25n=35n-90\\\\n+25n=35n-90\\\\26n=35n-90\qquad\text{subtrac 35 from both sides}\\\\-9n=-90\qquad\text{divide both sides by (-9)}\\\\n=10[/tex]
