Today, students studied the graph of quadratic equations y=ax^2+bx+c and understand the feature of the graphs in the shape of “parabola”, such as, leading coefficient “a” determines the graph open direction, upward or downward, vertex point represents the minimum point or maximum points, symmetric graph with the axis of symmetry passing through the vertex point. In order to figure out the feature easily, students learned to convert standard quadratic form ax^2+bx+c to vertex form a(x-h)^2+k, where (h,k) is vertex point, x=h is the axis of symmetry. To solve quadratic equation ax^2+bx+c=0 in graph method, plot y=ax^2+bx+c, then check if there is x-intercepts of the graph with x-axis that are the solution of the quadratic equation.
Here is the homework for today’s class:
P.414, 14.1.1, additionally find the solutions of quadratic equation when y=0
14.1.2, additionally find the solutions of quadratic equation when y=0