in the linear equation the greatest power of the variables is 1 for example:2X+4 this is a linearequationasthegreatestpowerofthevariableX is 1also by drawing it in a graph you will obtain a straight line
while in the quadratic equation the greatestpoweris2for instance:X^2+4X-3 this is a QuadraticequationbecausethegreatestpowerofthevariableX is 2also by drawing it on a graph you will obtain a parabola which is a curve "an upward curve or downward curve"
So product means multiplication so -2*(x-6) > -18 so divide by -2 on both sides to get x-6<9 because when you multiply a negative the sign swaps directions and then add 6 to get x<15
