Answer:
n = 1
Explanation:
I think you meant "the value of n." So we need to get n by itself, which means to "undo" anything that's acting on n:
2n + 19 = 21 To get rid of that 19, subtract it from both sides to get:
2n = 21 - 19 = 2 To get rid of the (2-times)n, divide both sides by 2:
2n/2 = 2/2
n = 1