If $2 x+6=16$, the value of $x+4$ is
(A) 7
(B) 8
(C) 9
(D) 15
(E) 13
Solution 1

Since $2 x+6=16$, then $\frac{2 x+6}{2}=\frac{16}{2}$ and so $x+3=8$.

Since $x+3=8$, then $x+4=(x+3)+1=8+1=9$.

Solution 2

Since $2 x+6=16$, then $2 x=16-6=10$.

Since $2 x=10$, then $\frac{2 x}{2}=\frac{10}{2}$ and so $x=5$.

Since $x=5$, then $x+4=5+4=9$.

ANSWER: (C)