A portion of a rectangle is shaded as shown. The area of the shaded region is 78 in? What is the value of x?
12 in.
8 in.
x in.
O x = 6
O x = 4
O X = 5
O X = 1.4

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