# Linear equations with one unknown

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This solution deals with linear equations with one unknown.

Solution found

a=6

- Linear equations with one unknown

## Step by Step Solution

### Rearrange:

Rearrange the equation by subtracting what is to the right of the equal sign from both sides of the equation :

3*(2*a-5)-(21)=0

## Step by step solution :

## Step 1 :

#### Equation at the end of step 1 :

```
3 • (2a - 5) - 21 = 0
```

## Step 2 :

## Step 3 :

#### Pulling out like terms :

3.1 Pull out like factors :

6a - 36 = 6 • (a - 6)

#### Equation at the end of step 3 :

```
6 • (a - 6) = 0
```

## Step 4 :

#### Equations which are never true :

4.1 Solve : 6 = 0

This equation has no solution.

A a non-zero constant never equals zero.

#### Solving a Single Variable Equation :

4.2 Solve : a-6 = 0

Add 6 to both sides of the equation :

a = 6