Find the angle which is double of its supplement.

Answer

To find the angle that is double its supplement, we can follow these steps:

### Step 1: Define the angle
Let the angle be represented as \( x \).

### Step 2: Define the supplement
The supplement of the angle \( x \) is given by \( 180^\circ - x \).

### Step 3: Set up the equation
According to the problem, the angle \( x \) is double its supplement. This can be expressed mathematically as:
\[ x = 2(180^\circ - x) \]

### Step 4: Simplify the equation
Now, we will simplify the equation:
\[ x = 2(180^\circ - x) \\ x = 360^\circ - 2x \]

### Step 5: Move all terms involving \( x \) to one side
To solve for \( x \), we can add \( 2x \) to both sides:
\[ x + 2x = 360^\circ \\ 3x = 360^\circ \]

### Step 6: Solve for \( x \)
Now, divide both sides by 3:
\[ x = \frac{360^\circ}{3} \\ x = 120^\circ \]

### Step 7: Conclusion
The angle that is double its supplement is \( 120^\circ \).

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