Solve the equation `x - 10 = 15,` State which axiom do you use here.

Answer

To solve the equation \( x - 10 = 15 \), we will follow these steps:

### Step 1: Identify the equation
We start with the equation:
\[ x - 10 = 15 \]

### Step 2: Add 10 to both sides
According to Euclid's second axiom, when equals are added to equals, the results are also equal. Here, we will add 10 to both sides of the equation to isolate \( x \):
\[ x - 10 + 10 = 15 + 10 \]

### Step 3: Simplify both sides
Now, simplify both sides of the equation:
\[ x = 25 \]

### Conclusion
The solution to the equation \( x - 10 = 15 \) is:
\[ x = 25 \]

### Axiom Used
The axiom used here is **Euclid's Second Axiom**, which states that if equals are added to equals, the results are equal.

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