Factoring
Solve the following quadratic equation.
(x - 7)(x + 2) = 0
x = 7 x = -2
or x = { 7, -2}
When solving quadratic equations, we are trying to find what feature of the parabola?
x-intercepts
What is the name of the graph for quadratic equations?
A parabola
Identify a, b and c in the following equation:
x2 + 6x - 5 = 0
a = 1; b = 6; c = -5
Solve the following quadratic equation by factoring.
x2 - 6x - 27 = 0
x = 9 x = -3
Why is the quadratic formula useful for solving quadratic equations?
We can ALWAYS use the quadratic formula, but we cannot always factor.
This line crosses the vertex of a parabola and divides the parabola into 2 equal halves.
Axis of Symmetry
Identify a, b and c in the following equation:
x2 - 9x + 20 = 9
a = 1; b = -9; c = 11
Solve the following quadratic equation by factoring. 2x2 - 5x - 3 = 0
x = -1/2 x = 3
How do we know a quadratic function does not have a real number solution when using the quadratic formula?
The number under the square root is negative
This point is the center of a parabola and can be a maximum or minimum, depending on the direction of the parabola.
Vertex
What is the quadratic formula?
x=(-b +- sqrt(b^2-4ac))/(2a)