Answer:
[tex] \boxed{ \bold{ \huge{ \boxed{ \sf{ n = 21}}}}}[/tex]
Step-by-step explanation:
[tex] \sf{n + 19 = 40}[/tex]
Move 19 to right hand side and change it's sign
⇒[tex] \sf{n = 40 - 19}[/tex]
Subtract 19 from 40
⇒[tex] \sf{n = 21}[/tex]
Hope I helped!
Best regards!!
