6-2 kites and trapezoids

Which equation results from adding the equations in this system? x+6y=9 and -x+2y=-15

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

Need plz been trying to do it for a long time and still haven’t succeeded