Good Morning !
So on Friday morning we covered a lot of different things, we reviewed our quizzes, revisited topics we have already learned as well as learning new things !
We started with looking at question # 1 on the "Quadratic Functions Complete the Square Pattern Activity"
Mr P. explained to us why (x+3)2 ≠ x2 + 9 . He also explained how it all leads back to algebra tiles...
(x+1)2 = x2 + 2x + 1 or (x + 1)2 = (x + 1)(x + 1)
This web site allows you to play around with the algebra tiles (:
http://nlvm.usu.edu/en/nav/frames_asid_189_g_4_t_2.html?open=activities&from=category_g_4_t_2.html
We discovered a pattern ...
ex.
(x+3)2 = x2 + 6x + 9 If you take the b variable (6) and divide it by 2 and then square it becomes the
(6/2)2 = 9 c variable (9)
ex.
x2 + 8x + 16
(8/2)2 = 16
We looked over the Complete the Square Worksheet, Mr P. explained three questions .
1. a2 + 16a + c (16/2)2 = 64 c = 64
2. n2 - 17n + c (-17/2)2 = 289/4 c=
3. y2 - 4/5y + c (-4/5/2)2 = (4/3 . 1/2) = (-4/10)2 reduces to (-2/5)2 = 4/25 c= 4/25
We Finished Class by learning two methods to complete the square .
Mr P's Favourite (Method One)
y= x2 + 6x + 8 Steps
1. Equate it all to zero
x2 + 6x + 8 = 0
2. Move c variable (8) to right hand side don't forget to change the sign !
x2 + 6x = -8
3. We want to Complete the Square . Divide b variable by 2 then square
(6/2)2 = 9 it to equal c variable.
x2 + 6x + 9 = -8 + 9 *What ever you do for the left side you must also do for the right.
make it equal out . *
x2 + 6x + 9 = 1 4. So we add 9 to both sides
* perfect square means it factors nicely *
(6/2)2 = 9 6/2 = 3 = (x + 3)2 = 1 Use value in bracket to factor (6/2 = 3)
5. Equate it all to zero again
(x + 3)2 - 1 = 0 6. Change back to vertex (standard) form
y = (x + 3)2 - 1 FINISHED (:
OR .
( Method Two. )rm
- using example one from the book.
y = x2 - 2x + 3 Take half of the middle term add to this equations subtract,
factor trinomial into a binomial
(-2/2)2 = 1
* Must subtract 1 because nothing is being moved *
y= ( x2 - 2x + 1) + 3 - 1
y= (x-1)2 + 2
H O M E W O R K
Complete the Square "Value of c worksheet"
Complete the Square Worksheet 2
Exercise Book ; Examples pg. 26,27,28 and Exercise 4 questions 1,2,9 and 10 .
If you don't understand Mr P gave the option of leaving out pg 27 ex. 3,4,5,6 for Monday .
Hope you guys had a great long weekend see you in class on Monday ! (:
- KristynOrvis .
No comments:
Post a Comment