complete the table and graph x (x - 3) 2 - 5 vertex
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Do NowComplete the table and graph
x (x - 3)2 - 5
Vertex

Answers to Homework1. y = ax2 + bx + c 2. y = a(x – h)2 + k3. y = -2x2 - 8x -15 4. y = (x – 2)2 + 4
8 8 242 2x
22 2 8 2 15y
2 4 16 15y
7y
: 2
: 2, 7
AOS x
V
: 2
: 2, 4
AOS x
V
5. y = (x + 9)2
: 9
: 9,0
AOS x
V
6. y = ½x2 + 6x + 5
12
6 6 612x
212 6 6 6 5y
12 36 36 5y
13y
: 6
: 6, 13
AOS x
V

Answers to Homework7. y = x2 + 2x + 5 8. y = x2 – 8
2 2 122 1x
21 2 1 5y
1 2 5 4y
1; : 1, 4a V
9. y = 2x2 + x
21 4y x
0 02 1
x
20 8 8y
1; : 0, 8a V 2 8y x
1 142 2
x
21 14 42y
1 1 1 2 116 4 8 8 82y
1 14 82; : ,a V
21 14 82y x
10. y = -2x2 + 8x + 3
8 8 242 2
x
22 2 8 2 3y
2 4 16 3 11y
2; : 2,11a V
22 2 11y x

Answers to Homework11. y = -(3x – 4)2 + 6 12. y = 2x(x + 7) + 8
3 4 3 4 6x x 22 14 8x x x 29 24 16 6x x
29 24 16 6x x 29 24 10y x x
22 22y x x
13. y = 4(x – 1)2 + 1 4 1 1 1x x
24 2 1 1x x
24 8 4 1x x 24 8 5y x x
14. y = (x + 1)2 – 7 1 1 7x x
2 2 1 7x x 2 2 6y x x

Answers to Homework15. Direction: Opens Up
Width: WideAOS: x = 2Vertex: (2, -1); Minimumy – intercept: (0, 0)# of Real Solutions: 2x – intercept: (4, 0) & (0, 0)Function? YesDomain: (-, )Range: [-1, )Rising: (2, )Falling: (, 2)
x ¼(x – 2)2 – 1
0 0
1 - ¾
2 -1
3 - ¾
4 0

Homework
Need Help? Look in textbook inSection 5.3: Translating Parabolas
Worksheet: Properties of Parabolas in Vertex Form

Unit 4: QuadraticsDay 18: Translating Parabolas

Unit 5: Quadratics
Objectives:Use vertex form to identify properties of parabolas

Vertex Form
What is vertex form?
2y a x h k

Properties of ParabolasDirection: Parabolas open up or open downDirection is determined by the sign of “a”
Open “up”a is positive
Open “down”a is negative
y = a(x - h)2 + k
22 32f x x 12
21 4y x

Properties of ParabolasWidth: Parabolas can be narrow, standard or wideWidth is determined by the value of a (not including the sign)
Narrow|a| > 1
Standard|a| = 1
Wide|a| < 1
y = a(x - h)2 + k
12
21 4y x 21 4y x 21 43y x

Properties of ParabolasAxis of Symmetry: The line that divides the parabola into two parts that are mirror imagesAOS is found using: Vertex: The point where the parabola passes through the AOSVertex is found by using:
Equation: a = 2, h = -1, k = -4AOS: x = – 1
Vertex: (-1, -4)Vertex is a minimum
y = a(x - h)2 + k
x h
22 1 4y x
,h k

Properties of Parabolasy – intercept: The point on the graph where the parabola intersects the y-axis.y – intercept is found by, making x = 0 and solving for y
Y – intercept will NOT the be “c” value as it is in standard form
Equation:
y -intercept: (0, -2)
22 0 1 4y
2 1 4y
y = a(x - h)2 + k
22 1 4y x
2y

Properties of ParabolasNumber of Real Solutions: The number of times the parabola intersects the x-axis on the real coordinate plane. Use the direction and the vertex to determine the number of real solutions
Picture the directionPicture the vertex on the graph
How many times will the parabola intersect the x-axis?
22 1 4y x 22y x 22 3 1y x
y = a(x - h)2 + k

Properties of Parabolasx – intercept(s): The point(s) on the graph where the parabola intersect the x - axis. Other names include: roots, zeroes and solutions.To find x – intercepts, make y = 0 and solve. Solve using square roots in vertex form.
y = a(x - h)2 + k
Equation:
x -intercept: (-1-√2, 0) & (-1+√2, 0)
22 1 4y x
20 2 1 4x
24 2 1x
22 1x
22 1x
2 1x
1 2 x

Solve the equation: 25 16y x 22 3 16y x 20 5 16x
216 5x
216 5x
4 5x 5 4 x
5 4 x 9 x 1 x 9,0 1,0
20 2 3 16x
216 2 3x
28 3x
28 3x
2 2 3i x 3 2 2i x
3 2 2i x 3 2 2,0i
3 2 2i x 3 2 2,0i
5 4 x

Properties of Parabolas
Operates the same in vertex and standard form:Function?: always passes VLTDomain: always (-, )Range: Depends on vertex and directionIntervals of Rising: Depends on vertex and directionIntervals of Falling: Depends on vertex and direction

Find all properties: Direction: _____________Width: ______________AOS: _________________Vertex: _______________
Max or Min? __________
y – int: _____________# of Real Solutions: ______x – int: _____________Function? __________Domain: ___________Range: _____________Rising: _____________Falling: ____________
Opens UpStandard
x = -7(-7, 0)
Minimum(0, 49)
Yes(-, )
[0, )(-7, )(-, -7)
27y x a is positive a =1x h 7
( , )h k 7,0
20 7y 27y
20 7x 0 7x
1
7 x
7,049

Find all properties: Direction: _____________Width: ______________AOS: _________________Vertex: _______________
Max or Min? __________
y – int: _____________# of Real Solutions: ______x – int: _____________Function? __________Domain: ___________Range: _____________Rising: _____________Falling: ____________
Opens DownWide/Stretched
x = 6(6, 3)
Maximum(0, -9)
Yes(-, )
(-, 3](-, 6)(6, )
213 6 3y x
a is negative a =1/3x h 6
( , )h k (6,3)
213 0 6 3y
213 ( 6) 3y
2130 6 3x
2133 6x
2
29 6x 3 6x
3 6x
9,0 & 3,09
9 x3 6x 3 x

Did you meet today’s objective?Name two properties you have to calculate differently in vertex form compared to standard form.