Yes scale factor means ratio. The height of the smaller pyramid to the larger pyramid in ratio form is 8:24 which simplifies to 1:3. The ratio of its areas is the scale factor squared, so 1^2:3^2=1:9. Since the surface area of the smaller pyramid is 124, the surface area of the larger pyramid must be 124x9. The ratio of volumes is the scale factor cubed, so 1^3:3^3=1:27. If the volume of the larger pyramid is 648, then the volume of the smaller pyramid is 1/27 of that, which equals 24.
We know the slope is -1, because perpendicular line's slopes are always the negative reciprocal. We plug (5, -3) in to get: -3 = -5 + b b = 2 So we get C. y = -x + 2. --- Hope this helps! ==jding713==
