Alexis has come up with the equation, f(x) = -2x + 20, to calculate how many bottles of lotion are left after assembling gift baskets. The variable x represents the number of gift baskets assembled and f(x) represents the number of bottles of lotion left. If 6 bottles of lotion are left, how many gift baskets were assembled?

Astudent draws two parabolas on graph paper. both parabolas cross the x-axis at (–4, 0) and (6, 0). the y-intercept of the first parabola is (0, –12). the y-intercept of the second parabola is (0, –24). what is the positive difference between the a values for the two functions that describe the parabolas? write your answer as a decimal rounded to the nearest tenth