Lesson 1.  Example 1. Use either elimination or the substitution method to solve each system of equations.  3x -2y = 7 & 2x +5y = 9  A. Using substitution.

Slides:



Advertisements
Similar presentations
Solve an equation with variables on both sides
Advertisements

Part 2.  Review…  Solve the following system by elimination:  x + 2y = 1 5x – 4y = -23  (2)x + (2)2y = 2(1)  2x + 4y = 2 5x – 4y = -23  7x = -21.
4 step by step on solving linear equations
Solve an equation using subtraction EXAMPLE 1 Solve x + 7 = 4. x + 7 = 4x + 7 = 4 Write original equation. x + 7 – 7 = 4 – 7 Use subtraction property of.
Standardized Test Practice
Solving Equations with variables on both sides of the Equals Chapter 3.5.
Lesson 2-4. Many equations contain variables on each side. To solve these equations, FIRST use addition and subtraction to write an equivalent equation.
3-4 Solving Systems of Linear Equations in 3 Variables
Standardized Test Practice
3.5 Solving systems of equations in 3 variables
Solving Systems of Linear Equations
Graphing Systems of Equations Graph of a System Intersecting lines- intersect at one point One solution Same Line- always are on top of each other,
( ) EXAMPLE 3 Standardized Test Practice SOLUTION 5 x = – 9 – 9
Systems of Equations: Elimination, Part II Unit 7, Lesson 5b.
SOLVING SYSTEMS ALGEBRAICALLY SECTION 3-2. SOLVING BY SUBSTITUTION 1) 3x + 4y = 12 STEP 1 : SOLVE ONE EQUATION FOR ONE OF THE VARIABLES 2) 2x + y = 10.
1.3 Solving Linear Equations
4.8 – Solving Equations with Fractions
Notes – 2/13 Addition Method of solving a System of Equations Also called the Elimination Method.
7.4. 5x + 2y = 16 5x + 2y = 16 3x – 4y = 20 3x – 4y = 20 In this linear system neither variable can be eliminated by adding the equations. In this linear.
Lesson 3.3 Solving Multi-step Equations Mr. Beltz & Mr. Sparks.
Solve an equation using addition EXAMPLE 2 Solve x – 12 = 3. Horizontal format Vertical format x– 12 = 3 Write original equation. x – 12 = 3 Add 12 to.
Example 1 Solving Two-Step Equations SOLUTION a. 12x2x + 5 = Write original equation. 112x2x + – = 15 – Subtract 1 from each side. (Subtraction property.
Warm Up Solve. 1. 3x = = z – 100 = w = 98.6 x = 34 y = 225 z = 121 w = 19.5 y 15.
Systems of Equations: Substitution
Use the substitution method
Solve Linear Systems by Substitution January 28, 2014 Pages
1. solve equations with variables on both sides. 2. solve equations with either infinite solutions or no solution Objectives The student will be able to:
Systems of Equations By Dr. Marinas. Solving Systems Graphing Method Substitution Method Elimination (or Adding) Method.
EXAMPLE 2 Solving an Equation Involving Decimals 1.4x – x = 0.21 Original equation. (1.4x – x)100 = (0.21)100 Multiply each side by 100.
7-3: Solving Systems of Equations using Elimination
Solve Equations With Variables on Both Sides. Steps to Solve Equations with Variables on Both Sides  1) Do distributive property  2) Combine like terms.
Elimination using Multiplication Honors Math – Grade 8.
6-2 Solving Systems Using Substitution Hubarth Algebra.
Solving Equations with Variables on Both Sides. Review O Suppose you want to solve -4m m = -3 What would you do as your first step? Explain.
Elimination Method - Systems. Elimination Method  With the elimination method, you create like terms that add to zero.
Substitution Method: Solve the linear system. Y = 3x + 2 Equation 1 x + 2y=11 Equation 2.
Rewrite a linear equation
3. 3 Solving Equations Using Addition or Subtraction 3
Section 1-3: Solving Equations 8/29/17
1. Add: 5 x2 – 1 + 2x x2 + 5x – 6 ANSWERS 2x2 +7x + 30
Example: Solve the equation. Multiply both sides by 5. Simplify both sides. Add –3y to both sides. Simplify both sides. Add –30 to both sides. Simplify.
EXAMPLE 2 Rationalize denominators of fractions Simplify
Solve Systems of Equations by Elimination
Preview Warm Up California Standards Lesson Presentation.
Solving Two-Step Equations
( ) EXAMPLE 3 Standardized Test Practice SOLUTION 5 x = – 9 – 9
Solving Systems Using Substitution
6-2 Solving Systems Using Substitution
Objective Solve equations in one variable that contain more than one operation.
Solving One-Step Equations
Solving Systems using Substitution
6-3 Solving Systems Using Elimination
Solve Systems of Equations by Elimination
3.5 Solving systems of equations in 3 variables
Solving Systems of Equations using Substitution
Lesson 2.1 How do you use properties of addition and multiplication?
EQ: How do I solve an equation in one variable?
Solve an equation by combining like terms
Solving Systems Check Point Quiz Corrections
Objectives Solve systems of linear equations in two variables by elimination. Compare and choose an appropriate method for solving systems of linear equations.
Two-Step Equations CA 5.0.
Solving Multi-Step Equations
Objective Solve equations in one variable that contain more than one operation.
Warm Up Solve for x. Simplify Simplify
Section Solving Linear Systems Algebraically
Example 2B: Solving Linear Systems by Elimination
Exercise Solve and check x – 3 = 5. x = 8 8 – 3 = 5.
If an equation contains fractions, it may help to multiply both sides of the equation by the least common denominator (LCD) to clear the fractions before.
Notes: 2-1 and 2-2 Solving a system of 2 equations:
By: Savana Bixler Solving Equations.
Presentation transcript:

Lesson 1

 Example 1. Use either elimination or the substitution method to solve each system of equations.  3x -2y = 7 & 2x +5y = 9  A. Using substitution method  3x -2y = 7 ( 1 st eq.)  2x +5y = 9 ( 2 nd eq.)

 1. Choose an equation to change either in y form or x form.  For example, I choose eq. 1 & change it to x form.  3x -2y = 7 ( 1 st eq.)  3x = 2y + 7   x = 3 rd equation

 2. Substitute the value of x in the 2 nd equation.  2( ) +5y = 9 ( 2 nd eq.)  Use distributive property  Multiply both sides by 3  4y y = 27

 Multiply both sides by 3  4y y = 27  by simplifying,  19y = 13  using division,  y =

 3. Find x by substituting the value of y in the 1 st equation or 3 rd eq. 3 rd equation By simplifying Get the LCD & simplify

 Example 1. Use either elimination or the substitution method to solve each system of equations.  3x -2y = 7 ( 1 st eq.)  2x +5y = 9 ( 2 nd eq.)  The solution set is

 A. Using elimination method  3x -2y = 7 ( 1 st eq.)  2x +5y = 9 ( 2 nd eq.)

 1. Choose a variable to eliminate.  For example, I choose x.  3x -2y = 7 ( 1 st eq.)  2x +5y = 9 ( 2 nd eq.)  To eliminate x, multiply the 1 st eq. by -2 and multiply the 2 nd eq. by 3. then add the 1 st eq. to the 2 nd eq..  -2(3x -2y = 7) ( 1 st eq.)  3(2x +5y = 9) ( 2 nd eq.)

 -6x + 4y = -14  + 6x +15y = 27  19y = 13  y = 13  19  2. Now substitute the value of y in either equation to find the value of x.

 I choose the 2 nd equation.  2x +5y = 9) ( 2 nd eq.)  Multiply both sides by 19  38 x + 65 = 171  38x = (subtract both sides by 65)

 38 x = 106 (by subtraction prop.)   X = 106 (by division prop.)  38  X = 53 (by simplifying)  19