Name:________________________________________________________________________________Date:_____/_____/__________
Quiz
Day!
1. Model the following equations:
x - (-2) = 5
x+3 = 1
x = ___
x = ___
2. Solve the following addition/subtraction one-step equations:
x + 24 = -6
4 = x + 54
x – 42 = -2
63 = x – (-1)
3. Solve the following multiplication/division one-step equations:
9x = -81
𝑥
−5
=9
4. Describe the “Golden Rule of Algebra.”
-100 = -20x
25 =
𝑥
3
Today’s Lesson:
What:
Two-step equations
Why:
To solve both multiplication and
division two-step equations.
What are Two-Step Equations??
Two-step equations are equations that
have ________________________
operations . In
two
other words, there are TWO numbers on
the same side with “x.”
To Solve a Two-Step Equation:
Step One: Add or subtract (zero pairs) to
constant
get rid of the __________________
.
Step Two: Multiply or divide to get rid of
coefficient
the ___________________
(or #
closest to “x”) .
Multiplication Two-Step Equations:
Example: 3x + 2 = 26
+(-2) +(-2) . . . (add “-2” to both sides
to make zero pair)
3x = 24
. . . (re-write equation)
3
...
3
x =8
(divide by 3 on both
sides)
Multiplication Guided examples:
1) 4x + -3 = 13
x =4
3) -20 – x = 5
x = -25
2)
31 = -5x – 4
x = -7
Your turn:
4) 5 + 3x = 20
x =5
5)
2 = 12 – x
x = 10
Division two-step equations:
Example:
𝑥
+ 3 = 13
−2
+(-3) +(- 3) . . . (add “-3” to both sides
to make zero pair)
𝑥
= 10 . . . (re-write equation)
−2
−𝟐
(
𝟏
𝑥
−𝟐
)
= 10( ) . . . (multiply by “flip”
𝟏
−2
on both sides)
x = -20
Division Guided examples:
1)
𝑥
2
2)
+ -7 = 11
x = 36
3)
𝑥+2
= -20
3
x = -62
2 =
𝑥
−3
- 6
x = -24
This one is different . . .
Multiply on both sides
by the denominator
FIRST!
Your turn:
𝑥+4
= -5
2
4)
x = -14
6) 3 +
𝑥
−5
= -7
x = 50
5)
21 =
𝑥
3
+ -4
x = 75
Let’s check out some Modeling with
two-step Equations . . .
Math Playground Equation Tool
Homework/ practice
Due by next class!
IXL: 7th Grade, T.6
(show work on
scratch paper)
END OF LESSON
The next slides are student copies of the notes for this
lesson. These notes were handed out in class and
filled-in as the lesson progressed.
Math-7 NOTES
NAME:
DATE: ______/_______/_______
What:
Two-step equations
Why:
To solve both multiplication and division two-step equations.
What are Two-Step Equations??
Two-step equations are equations that have _____________________ operations .
In other words, there are TWO numbers on the same side with “x.”
To Solve a Two-Step Equation:
Step One: Add or Subtract (zero pairs) to get rid of the ______________________.
Step Two: Multiply or divide to get rid of the _______________________.
Example:
3x + 2 = 26
+(-2) +( -2)
...
(add “-2” to both sides to make zero pair)
3x = 24
3
3
x =8
...
(re-write equation)
...
(divide by 3 on both sides)
Multiplication Guided examples:
1)
4x + -3 = 13
3)
-20 – x = 5
2)
31 = -5x – 4
5)
2 = 12 – x
Your turn:
4)
5 + 3x = 20
Division two-step equations:
Example: _x_ + 3 = 13
-2
+(-3) +(- 3)
...
(add “-3” to both sides to make zero pair)
_x_ = 10
. . . (re-write equation)
-2
−2
−2
( ) _x_ = 10( ) . . . (multiply by “flip” on both sides)
1
1
-2
x = -20
Division Guided examples:
1)
𝑥
2
3)
𝑥+2
3
+ -7 = 11
2)
2=
𝑥
−3
- 6
This one is different . . .
Multiply on both sides
by the denominator
FIRST!
= -20
Your turn:
4)
𝑥+4
= -5
2
5)
21 =
𝑥
3
+ -4
6)
3+
𝑥
−5
IXL: 7th Grade, T.6
= -7
NAME:_______________________________________________________________________________DATE: _____/_____/__________
Math-7 PRACTICE