Download presentation

Presentation is loading. Please wait.

Published byCeleste Bayse Modified over 3 years ago

1
**Solving Quadratic Equation by Graphing and Factoring**

Section 6.2& 6.3 CCSS: A.REI.4b

2
**Mathematical Practices:**

1. Make sense of problems and persevere in solving them. 2. Reason abstractly and quantitatively. 3. Construct viable arguments and critique the reasoning of others. 4. Model with mathematics. 5. Use appropriate tools strategically. 6. Attend to precision. 7. Look for and make use of structure. 8. Look for and express regularity in repeated reasoning.

3
CCSS: A.REI.4b SOLVE quadratic equations by inspection (e.g., for x2 = 49), taking square roots, completing the square, the quadratic formula and factoring, as appropriate to the initial form of the equation. RECOGNIZE when the quadratic formula gives complex solutions and write them as a ± bi for real numbers a and b.

4
Essential Question: How do I determine the domain, range, maximum, minimum, roots, and y-intercept of a quadratic function from its graph & how do I solve quadratic functions by factoring?

5
**Quadratic Equation y = ax2 + bx + c ax2__ is the quadratic term.**

bx--- is the linear term. c-- is the constant term. The highest exponent is two; therefore, the degree is two.

6
**Identifying Terms Example f(x)=5x2-7x+1 Quadratic term 5x2**

Linear term x Constant term 1

7
**Identifying Terms Example f(x) = 4x2 - 3 Quadratic term 4x2**

Linear term Constant term

8
**Identifying Terms Now you try this problem. f(x) = 5x2 - 2x + 3**

quadratic term linear term constant term 5x2 -2x 3

9
**Quadratic Solutions The number of real solutions is at most two.**

No solutions One solution Two solutions

10
Solving Equations When we talk about solving these equations, we want to find the value of x when y = 0. These values, where the graph crosses the x-axis, are called the x-intercepts. These values are also referred to as solutions, zeros, or roots.

11
**Identifying Solutions**

Example f(x) = x2 - 4 Solutions are -2 and 2.

12
**Identifying Solutions**

Now you try this problem. f(x) = 2x - x2 Solutions are 0 and 2.

13
**Graphing Quadratic Equations**

The graph of a quadratic equation is a parabola. The roots or zeros are the x-intercepts. The vertex is the maximum or minimum point. All parabolas have an axis of symmetry.

14
**Graphing Quadratic Equations**

One method of graphing uses a table with arbitrary x-values. Graph y = x2 - 4x Roots 0 and 4 , Vertex (2, -4) , Axis of Symmetry x = 2 x y 1 -3 2 -4 3 4

15
**Graphing Quadratic Equations**

Try this problem y = x2 - 2x - 8. Roots Vertex Axis of Symmetry x y -2 -1 1 3 4

16
**Graphing Quadratic Equations**

The graphing calculator is also a helpful tool for graphing quadratic equations.

17
**Roots or Zeros of the Quadratic Equation**

The Roots or Zeros of the Quadratic Equation are the points where the graph hits the x axis. The zeros of the functions are the input that make the equation equal zero. Roots are 4,-3

18
**To solve a Quadratic Equation**

Make one side zero. Then factor then set each factor to zero

19
Solve

20
Solve

21
Solve

22
Solve

23
Solve

24
Solve Solve

25
Solve Multiply the ends together and find what adds to the coefficient of the middle term

26
Solve Use -6 and 1 to break up the middle term

27
Solve Use group factoring to factor, first two terms and then the last two terms

28
Solve

29
**How to write a quadratic equation with roots**

Given r1,r2 the equation is (x - r1)(x - r2)=0 Then foil the factors, x2 - (r1 + r2)x+(r1· r2)=0

30
**How to write a quadratic equation with roots**

Given r1,r2 the equation is (x - r1)(x - r2)=0 Then foil the factors, x2 - (r1 + r2)x+(r1· r2)=0 Roots are -2, 5 Equation x2 - (-2+5)x+(-2)(5)=0 x2 - 3x -10 = 0

31
**How to write a quadratic equation with roots**

Roots are ¼, 8 Equation x2 -(¼+8)x+(¼)(8)=0 x2 -(33/4)x + 2 = 0 Must get rid of the fraction, multiply by the common dominator. 4 4x2 - 33x + 8 = 0

Similar presentations

OK

Warm up… You’ll need to pick up the worksheet up front. Remember how we used the calculator on Friday. Need to graph the vertex along with four other.

Warm up… You’ll need to pick up the worksheet up front. Remember how we used the calculator on Friday. Need to graph the vertex along with four other.

© 2017 SlidePlayer.com Inc.

All rights reserved.

Ads by Google

Ppt on 21st century skills common Ppt on different types of quadrilaterals and their properties Ppt on c language fundamentals ii Ppt on standing order activation Ppt on computer tips and tricks Marketing mix ppt on airtel Ppt on types of software system Fema ppt on cert training Presentation ppt on motivation and emotion Ppt on data collection methods in action