Answer:
B
Step-by-step explanation:
The expression can be written as

The - can be taken out from under the radicand and a 2 can be factored out of the expression to leave you with the expression

Hello from MrBillDoesMath!
Answer:
n = 5
Discussion:
Let the original number be "n" Translating the problem statement to mathematical symbolism:
n + 4 = 19 - 2n => add 2n to both sides
n + 2n + 4 = 19 - 2n + 2n => combine like terms
3n + 4 = 19 => subtract 4 from both sides
3n = 19 -4 = 15 => divide both sides by 3
n = 15/3 =5
Check: Does 5 +4 = 19 - 2(5)? Does 9 = 9? Yes. so the value for n is confirmed correct.
Thank you,
MrB