Determine the point-slope form of the line and the slope-intercept form of the line with x-intercept = -8 and y-intercept = -16

x-intercept = -8 and y-intercept = -16

means you have two points, (-8,0) and (0,-16)
slope = (-16-0)/(0+8) = -2

so y - 0 = -2(x + 8)
or y = -2x - 16