Solve Equations with Variables

Solving Equations with Variables on Both Sides

15 - x = 4x

15 - x + x = 4x + x

15 + 0x = 5x

15 = 5x

3 = x

x = 3

For example, we can add a quantity with a variable to both sides without changing the equation or the values that make it true:

5x = 6 + 2x

5x - 2x = 6 + 2x - 2x

3x = 6 + 0x

3x = 6

x = 2

Similarly, we can subtract a term with a variable from both sides of the equation:

Multiple Choice

Solve: 3x + 12=2x + 10

• -2

• 2

• -22

• 22

Multiple Choice

Solve: 3(2x + 2) = 4x - 6

• 6

• -6

• 10

• -10

Open Ended

What part of the video that we watched today made this lesson 'click' for you? Was it the colored equations? Was it the explanations? What part of the explanation helped you understand this topic the most?