Answer:

here's your answer

Explanation:

f, the focal length, is positive for a concave mirror, and negative for a convex mirror.When the image distance is negative, the image is behind the mirror, so the image is virtual and upright. A negative m means that the image is inverted. Positive means an upright image. You can get this this clearly when you plot the attached image on a graph. When you do so you get the focal length of a convex in the negative quadrant and the focal length of a convex mirror on the positive quadrant.