Quadratic Formula Using the Quadratic formula to solve a quadratic. Practice of quadratic applications involving the quadratic formula. Activity Quadratic formula to solve | Mixed problems (www.transum.org)  Ex6.06, Ex 6.05 Illuminations completing the square Theta pg 24 NuLake EAS Q398 - 419 GeoGebra Java G Quadratic Applications Forming a quadratic equation from an applivation problem. Solving quadratic problems in context.  Ex6.07, Ex 6.08 Theta pg 25 NuLake EAS Q393 - 397 & 418, 419 21 Nature of roots Establishing the nature of roots & using the discriminant to determine if there are none, one or two solutions (roots) to a quadratic problem  Ex6.09, Ex6.10 Theta pg 26 NuLake EAS Q420 - 440 Graph intersections Finding the points of intersection between lines & parabolas, circles, hyperbola. Solving simultaneous equations involving substitution and solving a quadratic by factorising, completing the square, or the quadratic formula. Applications of intersections and problems in context  Ex7.01, Ex7.02, Ex7.03 points of intersection Theta pg 27 & 28 NuLake EAS Q441- 445 Intersections Determining the points of intersection between functions: line & parabola,  line & circle, line & hyperbola, Tangency Blank notes | Absolute value graphs bland notes Khan Academy Solving Quadratics

### To solve a quadratic equation the factorising can be very difficult. The quadratic formula finds the solutions avoiding the factorising process. Be careful with negatives.

###### Investigating the quadratic formula and the quadratic graph roots (Thanks to Sue Berg)
 The quadratic formula An example Working Solution 2nd example Working SolutionMouse over key words  ### Summary:

example 1 example 2    # The Descriminant

### The part of the quadratic formula in the square root is the descriminant. This tells us if there is one, two or no (real) solutions

 The quadratic formula The descriminant Two solution One solutions No (real) solutionsMouse over key words  ### Summary:   