week 6 – precalc 11

This week we started a new unit of solving quadratic equations.  last week was mostly a review for the harder lessons we had this week.  in lesson 3.2 we started by solving quadratic equations by using the zero product law.

x^2-6x+5=0

 

(x-1)(x-5)

 

x= 1, 5

 

Verify :

5^2-6(5)+5=0

 

In lesson 3.3 we learned how to solve perfect square trinomials by completing the square.  remembering to put a plus and a minus symbol when adding a radical is an important step when solving and verifying.

 

x^2+4x=2

 

$latex x^2+4x-2=0

 

(x+2)^2-6=0

 

(x+2)^2=6

 

x=-2 \pm \sqrt{6}