ONE STEP EQUATIONS Addition and Subtraction Equations Multiplication and Division Equations.
Lesson 2-4. Many equations contain variables on each side. To solve these equations, FIRST use...
-
Upload
sydney-hill -
Category
Documents
-
view
214 -
download
0
Transcript of Lesson 2-4. Many equations contain variables on each side. To solve these equations, FIRST use...
![Page 1: Lesson 2-4. Many equations contain variables on each side. To solve these equations, FIRST use addition and subtraction to write an equivalent equation.](https://reader036.fdocuments.in/reader036/viewer/2022082710/56649db45503460f94aa5331/html5/thumbnails/1.jpg)
Solving Equations with Variables on
Both SidesLesson 2-4
![Page 2: Lesson 2-4. Many equations contain variables on each side. To solve these equations, FIRST use addition and subtraction to write an equivalent equation.](https://reader036.fdocuments.in/reader036/viewer/2022082710/56649db45503460f94aa5331/html5/thumbnails/2.jpg)
Many equations contain variables on each side. To
solve these equations, FIRST use addition and
subtraction to write an equivalent equation with all of
the variables on one side.
Traditionally, the variables (letter) are “moved to the
___________________ and the constants (numbers)
are “moved” to the ________________ side of the
equal sign.
left
right
![Page 3: Lesson 2-4. Many equations contain variables on each side. To solve these equations, FIRST use addition and subtraction to write an equivalent equation.](https://reader036.fdocuments.in/reader036/viewer/2022082710/56649db45503460f94aa5331/html5/thumbnails/3.jpg)
A. 8 + 5s = 7s – 2
_________________________________ subtract “7s” so variables are on the left.
_________________________________ Simplify
___________________________________ Subtract “8” so constants are on the right.
___________________________________ Simplify
___________________________________ Multiply/Divide
___________________________________ Simplify
CHECK:
__________________________________
___________________________________
____________________________________
8 + 5s – 7s = 7s – 7s – 2
8 – 2s = – 2
8 – 8 – 2s = – 2 – 8
– 2s = – 10
s = 5
8 + 5(5) = 7(5) - 2
Substitute the value of the variable for the
variable
8 + 25 35 - 2
33 33
![Page 4: Lesson 2-4. Many equations contain variables on each side. To solve these equations, FIRST use addition and subtraction to write an equivalent equation.](https://reader036.fdocuments.in/reader036/viewer/2022082710/56649db45503460f94aa5331/html5/thumbnails/4.jpg)
Multiply both sides by the LCD
12 – r = 2r + 3 Simplify using the distributive property.
12 – r – 2r = 2r – 2r + 3 Subtract 2r from each side, this “moves” the variable to the left side of the equation.12 – 3r = 3 -r -2r = -3r
12 – 12 – 3r = 3 – 12 Subtract 12 from each side, this “moves” the constant to the right side of the equation.
– 3r = – 9 Simplify “3 – 12”
Divide each side by -3 (coefficient of r)
r = 3 Simplify
![Page 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.](https://reader036.fdocuments.in/reader036/viewer/2022082710/56649db45503460f94aa5331/html5/thumbnails/5.jpg)
CHECK:
3 – 0.75 1.5 + 0.75
2.25 2.25
Since the two sides are the same, the equation checks.
![Page 6: Lesson 2-4. Many equations contain variables on each side. To solve these equations, FIRST use addition and subtraction to write an equivalent equation.](https://reader036.fdocuments.in/reader036/viewer/2022082710/56649db45503460f94aa5331/html5/thumbnails/6.jpg)
Practice solving the problems below. Answers are on the last slide of the part 2 notes.
![Page 7: Lesson 2-4. Many equations contain variables on each side. To solve these equations, FIRST use addition and subtraction to write an equivalent equation.](https://reader036.fdocuments.in/reader036/viewer/2022082710/56649db45503460f94aa5331/html5/thumbnails/7.jpg)
Solving Equations with Grouping Symbols
6 + 4q = 12q - 42
6 + 4q – 12q = 12q – 12q - 42
6 – 8q = - 42
6 – 6 – 8q = – 42 – 6
– 8q = – 48
q = 6
30 = 30
CHECK:
![Page 8: Lesson 2-4. Many equations contain variables on each side. To solve these equations, FIRST use addition and subtraction to write an equivalent equation.](https://reader036.fdocuments.in/reader036/viewer/2022082710/56649db45503460f94aa5331/html5/thumbnails/8.jpg)
Yes, there is a “typo” in your notes.
18r – 24 = 21r + 3
18r – 24 – 21r = 21r – 21r + 3
– 3r – 24 = 3
– 3r – 24 + 24 = 3 + 24
– 3r = 27
r = – 9
Use the distributive property.
Subtract 21r from each side to eliminate the variables on the right side..Simplify by combining Like Terms (18r and -21r).
Add 24 to each side to eliminate the constants on the left side.
Simplify (add 3 + 24)
Divide each side by -3 (the coefficient of r.)
Simplify
![Page 9: Lesson 2-4. Many equations contain variables on each side. To solve these equations, FIRST use addition and subtraction to write an equivalent equation.](https://reader036.fdocuments.in/reader036/viewer/2022082710/56649db45503460f94aa5331/html5/thumbnails/9.jpg)
Check:
![Page 10: Lesson 2-4. Many equations contain variables on each side. To solve these equations, FIRST use addition and subtraction to write an equivalent equation.](https://reader036.fdocuments.in/reader036/viewer/2022082710/56649db45503460f94aa5331/html5/thumbnails/10.jpg)
Practice solving the problems below. Answers are on the last slide of the part 2 notes.
![Page 11: Lesson 2-4. Many equations contain variables on each side. To solve these equations, FIRST use addition and subtraction to write an equivalent equation.](https://reader036.fdocuments.in/reader036/viewer/2022082710/56649db45503460f94aa5331/html5/thumbnails/11.jpg)
Please check back for part 2 of these notes where we investigate equations that
have no solution or infinitely many solutions.