NEED HELP ASAP!! Which system of equations is represented by this graph?

a y=-2/5x-4

y=-3x+2

b y=-2/5x+2

y=-3x-4

c y=-5/2x-4

y=-1/3x+2

d y=-5/2x+2

y=-1/3x-4

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