How do you solve -1+ 8n + 4= 19?

May 31, 2018

$n = 2$

Explanation:

1. Sum similar terms: $\textcolor{red}{- 1} + 8 n \setminus \textcolor{red}{+ 4} = 19 \setminus \to 8 n + 3 = 19$
2. Isolate the term involving the variable on the left: to do so, subtract $3$ from both sides: $8 n + 3 \setminus \textcolor{red}{- 3} = 19 \setminus \textcolor{red}{- 3}$. The equation becomes $8 n = 16$
3. Solve for the variable. To do so, divide both sides by $8$: $\setminus \frac{8 n}{\setminus \textcolor{red}{8}} = \setminus \frac{16}{\setminus \textcolor{red}{8}} \setminus \to n = 2$
May 31, 2018

$x = 2$

Explanation:

Using Distributive Property..

$- 1 + 8 n + 4 = 19$

Firstly, collecting like terms on the LHS only;

$- 1 + 4 + 8 n = 19$

$3 + 8 n = 19$

Secondly, subtract $3$ from both sides;

$3 + 8 n - 3 = 19 - 3$

$3 - 3 + 8 n = 19 - 3$

$0 + 8 n = 16$

$8 n = 16$

Thirdly, divide both sides by the coefficient of $n$

$\frac{8 n}{8} = \frac{16}{8}$

$\frac{\cancel{8} n}{\cancel{8}} = \frac{16}{8}$

$x = \frac{16}{8}$

$x = 2$