Chapter 2.4 Equations with variables on both sides

Example 1- Variables on both sides!

To solve and equation with variables on both sides add or subtract to get them on the same side of the equation.

ex. 5x-4=2x+8

-2x -2x

3x-4=8

Then get the numbers on each side.

ex. 3x-4=8

+4 +4

3x=12

Next Divide the variable number from the variable.

ex. 3/3x=12/3

x=4

Example 2- Real World Problem Solving!

ex. Cincinnati Bell charges $32.95 per month and .02 per minute for local calls. Verizon charges $14.95 per month and .05 per minute for each local call. What number of minutes of local call per month make the cost the same.

First you have to make an equation.

ex. 32.95+.02x=14.95+.05x

Then you can solve the equation.

ex. 32.95+.02x=14.95+.05x

-.02x -.02x

32.95=14.95+.03x

-14.95 -14.95

18/.03=.03x/.03

600 minutes

Example 3- Identities and Equations with No Solutions!

An equation with no solution has if no value makes it true.

An identity is true for every value.

ex. identity

10s-6=10s-6

6=6

ex. no solution

8m-5=8m+7

-5=7