Isolate the Variable
Date: 9/9/96 at 16:21:50 From: Anonymous Subject: Simplifying Equations of Numbers, Variables Dear Dr. Math What are the steps needed to solve: 4c + 23 = 9c - 7
Date: 9/9/96 at 22:12:3 From: Doctor Ana Subject: Re: Simplifying Equations of Numbers, Variables I'm going to solve a different problem to show you how to solve this type of problem. There is only one big thing to remember, and that is to ISOLATE the variable. 5x - 17 = -x + 7 The first step to isolating the variable is to get any term with the variable in it on one side of the equation. To do this, we are going to add x to both sides of the equation. 5x - 17 + x = -x + x + 7 This simplifies to 6x - 17 = 7 The next step is to get rid of everything else that is on the same side of the equation as the variable. To do this, we will add 17 to both sides of the equation. 6x - 17 + 17 = 7 + 17 This simplifies to 6x = 24 Finally, the only thing left with the variable is the coefficient of 6. To completely isolate the variable, we have to divide both sides of the equation by 6. x = 24 / 6 x = 4 Now, x is all by itself or "isolated". We can read the answer right from the equation. x equals 4. To review, isolating the variable means getting every term containing the variable on one side of the equation. Then, get any term that doesn't contain the variable on the other side of the equation. Finally, combine any terms that aren't already combined, and get rid of the coefficient of the variable, if there is one. -Doctor Ana, The Math Forum Check out our web site! http://mathforum.org/dr.math/
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