1) Solve X 16 = 17

1
1) Solve X 16 17

• Think of this equation as a balance scale.

2
Key Terms
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Variable
In the problem X 5 8, X is the variable.
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Opposite
Opposites tall, short heavy, light addition,
subtraction multiplication, division
Isolate
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In the problem x y 2, the X is isolated.
3
1) Solve X 16 !7

• To solve, you must isolate the variable.
• What number is on the same side as X?
• 16
• To get X by itself (isolate), we must undo the
  add 16. What is the opposite of addition?
• Subtract 16

4
1) Solve X 16 17
- 16 -16 X 1 1 16 17

1. Draw the river to separate the equation into 2
   sides
2. Subtract 16 from both sides
3. Check your answer

5
2) Solve X 2 15What is your first step?

1. Add 2 to both sides
2. Subtract 2 from both sides
3. Add 15 to both sides
4. Subtract 15 from both sides

6
2) Solve x 2 15
- 2 - 2 x 13 13 2 15

1. Draw the river to separate the equation into 2
   sides
2. Subtract 2 from both sides
3. Check your answer

On homework and tests, be sure to check your
work!! There is no reason why you should miss a
problem!
7
3) Solve 8 X - 3
3 3 11 X 8 11 - 3

1. Draw the river to separate the equation into 2
   sides
2. Add 3 to both sides
3. Check your answer

8
Independent Practice
Answers
X 4 8
X 12
2 X - 3
X 5
X 10 82
X 72
18 X 9
X 9