The well-known equation 
linear or anything we have seen before. It has a shape of spaceship’s top head part. It is
divided to upper graph and down graph. If it is upper graph which is also Called up-opened
graph has a value a of negative value. Although if it is down graph which is also said down-
opened graph has a value of a as an positive value. Now we have a choice of what a value would
be, lets find b and c value. what graph will be looks like when b is negative value? well if
it is, graph goes to right side of y-axis. For example, 
(1,0) as an vertex and graph goes to right side of y-axis. In the opposite, $latex x^2 + 2x +
1 $ is graphed as a left side of y-axis. Finally, c is chosen by graph shape with y-
intercept. The point that matches with y-axis is related to c value because if the point is in
the y-axis, x value has to be 0 so a * 0 * 0 + b * 0 + c = 0 + 0 + c = c. If the c value is
negative, y-intercept of that graph is negative. If the c value is positive, y-intercept of
that graph is positive.