The image you uploaded is rotated sideways, but I can still analyze it. The specific part you referred to seems to be "15," which might be the problem number. However, the content of the problem isn't fully clear from the image.

If you could clarify the equation or problem that you would like to solve from this image, I would be happy to assist you further. Alternatively, you could provide more details or a better quality image.

Would you like to clarify the problem, or should I attempt to adjust the image to read it more clearly?