a particle moves along the x-axis so that its velocity in feet per second at time x, in seconds, is modeled by the quadratic function y = 2x2  − 10x + 12. what does the number 12 represent for the quadratic function?   the particle is 12 feet above the x-axis initially.  the particle's initially velocity is 12.  the particle is 12 feet to the left of the origin initially.  the particle's terminal velocity is 12.