## ← Check Against Excluded Values - Visualizing Algebra

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Showing Revision 2 created 05/24/2016 by Udacity Robot.

1. Since this equation is linear, we can use our skills from before. We solve the
2. equation by grouping the variable terms on one side, and the constant terms on
3. the other. We subtract 4 from both sides first to get negative 3x equals
4. positive 3. Then we divide both sides by negative 3 to get x is equal to
5. negative 1. This is our answer, and for these types of problems we're going to
6. write the answer as a solution set. So this would be the solution set to our
7. original equation. Once we find our solution, we want to make sure we always
8. check it against the excluded values. For this equation, we knew x cannot equal
9. 0, so this solution set is okay, since x could equal negative 1. And like all of
10. our other equations, we can check to make sure that we're right. We plug in a
11. value of negative 1 for x here and here. When I simplify the equation, I'll have
12. negative 3 and a half on the left and negative 3 and a half on the right. So
13. yes, this is correct.