Question

If N=10 then what is 2n+4

Answer 1

if n is ten then the expression would change to 
2(10)+4
20+4
so your answer would be 24

Answer 2

2n+4 is 24 because when you plug in the variable it makes the expression (2)(10)+4, so you simplify that by multiplying 2 and 10 and then add 4 to get 24