Solve {l}{text{Solve.}}{text{a)}7n+5[n-(n-4)]=n+12-4n}

$$\left. \begin{array} { l } { \text { Solve. } } \\ { \text { a) } 7 n + 5 [ n - ( n - 4 ) ] = n + 12 - 4 n } \end{array} \right.$$

Solve for n

$$n=-\frac{4}{5}=-0.8$$

Steps for Solving Linear Equation

To find the opposite of n-4, find the opposite of each term.

$$7n+5\left(n-n-\left(-4\right)\right)=n+12-4n$$

The opposite of -4 is 4.

$$7n+5\left(n-n+4\right)=n+12-4n$$

Combine n and -n to get 0.

$$7n+5\times 4=n+12-4n$$

Multiply 5 and 4 to get 20.

$$7n+20=n+12-4n$$

Combine n and -4n to get -3n.

$$7n+20=-3n+12$$

Add 3n to both sides.

$$7n+20+3n=12$$

Combine 7n and 3n to get 10n.

$$10n+20=12$$

Subtract 20 from both sides.

$$10n=12-20$$

Subtract 20 from 12 to get -8.

$$10n=-8$$

Divide both sides by 10.

$$n=\frac{-8}{10}$$

Reduce the fraction \frac{-8}{10} to lowest terms by extracting and canceling out 2.

$$n=-\frac{4}{5}$$