This week we learned about the different forms in which a quadratic equation can be written.
So far we have only been practising with what is known as the vertex form. This followed the pattern: y=
There is also the standard form: y=a
And we also occasionally use factored form: y=a(x-r1)(x-r2)
The vertex form (also know as general form) is, as it implies, used for finding the vertex. It is also called graphing form because once we have this form, we know what our vertex is and therefore we can graph from there.
Standard for is less used because it doesn’t give us much information but it is important later on. We can find out the y-intercept by looking at the last term.
Factored form allows us to find the x-intercepts because we can find x when it is equal to 0.
And we can also convert between these forms:
-To go from standard form to vertex form, we have to complete the square
-To go from Standard to Factored, we factor
-To return from Factored to Standard we FOIL.