Transcript Solving Equations with Addition and Subtraction

Solve equations using addition and
subtraction.
https://www.youtube.com/watch?v=W7fPsSw74TM
1) Solve r + 16 = -7
Think of this equation as a balance scale.
Whatever you do to one side
has to be done to the other to
keep it balanced!
1) Solve r + 16 = -7
To solve, you must get the variable by itself.
What number is on the same side as r?
16
To get r by itself, we must undo the “add 16”.
What is the opposite of adding 16?
Subtracting 16
2.
1) Solve r + 16 = -7
Draw a wall to
16
-16
separate the equation
into 2 sides
r
=
-23
Subtract 16 from both
3.
sides
Write your answer
1.
2) Solve x + 2 = -3
Get the variable by itself.
What is your first step?
1.
2.
3.
4.
Add 2 to both sides
Subtract 2 from both sides
Add 3 to both sides
Subtract 3 from both sides
Answer Now
2.
2) Solve x + 2 = -3
Draw “the wall” to
2
2
separate the equation
into 2 sides
x
=
-5
Subtract 2 from both
3.
sides
Write the answer
1.
3) Solve 8 = m - 3
1.
2.
3.
4.
m=5
m = 11
m = 24
m = 8/3
Answer Now
3) Solve 8 = m - 3
+3
+3
11= m
4) Solve y + -3 = 7
- -3
y
- -3
= 10
5) Solve. x - -2 = 1
+ -2 + -2
x
= -1
Solve y – -3 = 7
1.
2.
3.
4.
y = 10
y=4
y = -10
y = -4
Answer Now