SOLVING QUADRATIC EQUATIONS
Learning Objective
At the end of the session, student should be able to solve quadratic equations by:
a. Extracting Square Roots
b. Factoring
c. Completing the Square
d. Quadratic Formula
Solving Quadratic Equations
Ways to solve quadratic equations. (solve for x or finding the roots of the
equation)
1. Extracting the Square Roots
2. Factoring
3. Completing the Square
4. Using Quadratic Formula
5. Graphing
KICKSTARTER: Know My Values
Find the values of a, b and c in the following quadratic equations. (page 10)
Solving Quadratic Equations by Extracting the Square Roots
Rule: The Square Root Principle (SRP)
If
Solving Quadratic Equations by Extracting the Square Roots
Example: Solve for x (find the roots of the equation)
using the SRP
simplifying the radical
The two solutions (roots) are 2 and - 2.
Solving Quadratic Equations by Extracting the Square Roots
Example: Solve for x (find the roots of the equation)
using the SRP
simplifying the radical
The two solutions (roots) are 7 and - 7.
Solving Quadratic Equations by Extracting the Square Roots
Example: Solve for x (find the roots of the equation)
Subtracting 3 to both sides
Simplify both sides
using the SRP
factor the radicand
simplifying the radical
The two solutions (roots) are and .
Perfect
Square
Solving Quadratic Equations by Extracting the Square Roots
Example: Solve for x (find the roots of the equation)
Perfect
Square
Add 9 to both sides
Simplify both sides
divide both sides by 4
Simplify both sides
using the SRP
factor the radicand
simplifying the radical
The two solutions (roots) are and .
Solving Quadratic Equations by Extracting the Square Roots
Example: Solve for x (find the roots of the equation)
isolate the term containing quadratic
apply the square root property
simplify the radical
isolate the variable x
𝒙𝟏=𝟓+𝟏𝟎=𝟏𝟓
𝒙𝟐=𝟓 −𝟏𝟎=−𝟓
The roots are -5 and 15.
Solving Quadratic Equations by Extracting the Square Roots
Example: Solve for x (find the roots of the equation)
isolate the term containing quadratic
apply the square root property
simplify the radical
isolate the variable x
𝒙 𝟏=𝟐+𝟐 √𝟑
𝒙 𝟐=𝟐 −𝟐 √𝟑
The roots are
factor the radical
Perfect
Square
Solving Quadratic Equations by Extracting the Square Roots
Example: Solve for x (find the roots of the equation)
using the SRP
add 3 to both sides
simplify both sides
divide both sides by 5
simplify both sides
𝒙=
𝟑± √𝟏𝟔 √− 𝟐
𝟓
𝒙=
𝟑 ± 𝟒 √−𝟐
𝟓
Because the square root of a
negative number is not a real
number, there is no real number to
the given equation.
Activity: It’s in My Roots!!
Solve the following quadratic equations (pages 12-13).

Module-2.1-Solving-Quadratic-Equations-SRP.pptx

  • 1.
  • 2.
    Learning Objective At theend of the session, student should be able to solve quadratic equations by: a. Extracting Square Roots b. Factoring c. Completing the Square d. Quadratic Formula
  • 3.
    Solving Quadratic Equations Waysto solve quadratic equations. (solve for x or finding the roots of the equation) 1. Extracting the Square Roots 2. Factoring 3. Completing the Square 4. Using Quadratic Formula 5. Graphing
  • 4.
    KICKSTARTER: Know MyValues Find the values of a, b and c in the following quadratic equations. (page 10)
  • 5.
    Solving Quadratic Equationsby Extracting the Square Roots Rule: The Square Root Principle (SRP) If
  • 6.
    Solving Quadratic Equationsby Extracting the Square Roots Example: Solve for x (find the roots of the equation) using the SRP simplifying the radical The two solutions (roots) are 2 and - 2.
  • 7.
    Solving Quadratic Equationsby Extracting the Square Roots Example: Solve for x (find the roots of the equation) using the SRP simplifying the radical The two solutions (roots) are 7 and - 7.
  • 8.
    Solving Quadratic Equationsby Extracting the Square Roots Example: Solve for x (find the roots of the equation) Subtracting 3 to both sides Simplify both sides using the SRP factor the radicand simplifying the radical The two solutions (roots) are and . Perfect Square
  • 9.
    Solving Quadratic Equationsby Extracting the Square Roots Example: Solve for x (find the roots of the equation) Perfect Square Add 9 to both sides Simplify both sides divide both sides by 4 Simplify both sides using the SRP factor the radicand simplifying the radical The two solutions (roots) are and .
  • 10.
    Solving Quadratic Equationsby Extracting the Square Roots Example: Solve for x (find the roots of the equation) isolate the term containing quadratic apply the square root property simplify the radical isolate the variable x 𝒙𝟏=𝟓+𝟏𝟎=𝟏𝟓 𝒙𝟐=𝟓 −𝟏𝟎=−𝟓 The roots are -5 and 15.
  • 11.
    Solving Quadratic Equationsby Extracting the Square Roots Example: Solve for x (find the roots of the equation) isolate the term containing quadratic apply the square root property simplify the radical isolate the variable x 𝒙 𝟏=𝟐+𝟐 √𝟑 𝒙 𝟐=𝟐 −𝟐 √𝟑 The roots are factor the radical Perfect Square
  • 12.
    Solving Quadratic Equationsby Extracting the Square Roots Example: Solve for x (find the roots of the equation) using the SRP add 3 to both sides simplify both sides divide both sides by 5 simplify both sides 𝒙= 𝟑± √𝟏𝟔 √− 𝟐 𝟓 𝒙= 𝟑 ± 𝟒 √−𝟐 𝟓 Because the square root of a negative number is not a real number, there is no real number to the given equation.
  • 13.
    Activity: It’s inMy Roots!! Solve the following quadratic equations (pages 12-13).