Range is the y values or ouputs domain is inputs or x vvalues
we can use any x value but at a certain y value, w can't go below that find thatminimum find the vertex for ax^2+bx+c the x value of the vertex is -b/2a plug that in to the equaiton to get the y value
-b/2a=-(-6)/(2*2)=6/4=3/2
plug that in 2(3/2)^2-6(3/2)-9 2(9/4)-9-9 9/2-18 4.5-18 -13.5
domain=all real numbers range=from -13.5 to positive infinity
