Make an equation that will work for the given sentence.
The sum of 4 and x is 15.
The equation that will work for the given sentence is: `4 + x = 15`
Complete the following task based on the instruction and optional input provided.### Instruction:
Make an equation that will work for the given sentence.

### Input:
The sum of 4 and x is 15.

### Output:
The equation that will work for the given sentence is: `4 + x = 15`