Section 1.5 Quadratic Equations

Solving Quadratic Equations by Factoring

Example Solve by factoring:

Example Solve by factoring:

Example Solve by factoring:

Graphing Calculator The real solutions of a quadratic equation ax 2 +bx+c=0 correspond to the x-intercepts of the graph. The U shaped graph shown below has two x intercepts. When y=0, the value(s) of x will be the solution to the equation. Since y=0 these are called the zeros of the function.

Solving Polynomial Equations using the Graphing Calculator Repeat this process for each x intercept. By pressing 2 nd Trace to get Calc, then the #2,you get the zeros. It will ask you for left and right bounds, and then a guess. For left and right bounds move the blinking cursor (using the arrow keys-cursor keys) to the left and press enter. Then move the cursor to the right of the x intercept and press enter. Press enter when asked to guess. Then you get the zeros or solution.

Solving Quadratic Equations by the Square Root Property

Example Solve by the square root property:

Example Solve by the square root property:

Completing the Square

Why we call this completing the square.

Example What term should be added to each binomial so that it becomes a perfect square trinomial? Write and factor the trinomial.

Example Solve by Completing the Square:

Example Solve by Completing the Square:

Solving Quadratic Equations Using the Quadratic Formula

Determining Which Method to Use

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