I guess one way to do it is:
So the graph would be translated units to the right. But in your graph the vertex is to the left, and is negative. Therefore must be positive.
The diagram shows part of the graph of the function: y=ax^2+bx+c.
(seeing as I cannot draw the diagram here, it is basically an upside down parabola, with the vertex on the x-axis, and the whole parabola is in the fourth quadrant)
State whether each of the following expressions is positive, negative or zero.
a) a negative
b) c negative
c) b^2-4ac zero
d) b ?
I cannot figure out how to find whether constant b is positive, negative or zero. Can someone help me?