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Question 557361: If 3x+c=4, then x equals what?
How do you do the above problem?
Found 2 solutions by Theo, bucky:
Answer by Theo(13342)   (Show Source):
You can put this solution on YOUR website! 3x + c = 4
subtract c from both sides of the equation to get:
3x = 4 - c
divide both sides of the equation by 3 to get:
x = (4-c)/3
that's if you are solving for x.
if you are solving for c, you would do the following:
3x + c = 4
subtract 3x from both sides of the equation to get:
c = 4 - 3x
Answer by bucky(2189)  (Show Source):
You can put this solution on YOUR website! You are asked to solve for x in the given equation:
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The first thing to recognize is that the equation has two unknowns, x and c. You cannot solve this single equation to determine a numerical value for x. In order to get a numerical value for x you need to know a numerical value for c, and to solve for two unknowns (x and c) you need to be given two independent equations.
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So in this problem, when you solve for x, you will do so knowing that the c will still be involved in determining x.
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Here's what is involved in answering this problem:
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First, you need to get the term involving x to be the only term on the left side, meaning that all other terms need to be on the right side.
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So you need to move the + c to the right side of the equation. You can do this by subtracting c from both sides. This is done as follows:
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On the left side the + c and the - c cancel each other and that makes the + c disappear from the left side. The equation that remains after this subtraction is:
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Finally, you solve for x by dividing both sides of this equation (all terms) by 3. On the left side, when you divide 3x by 3 you are left with just x. On the right side the division by 3 can be written as shown:
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This answer can also be written as:
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Both answers are the same, just in different forms.
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This tells you that in order to get a numerical answer for x, you have to be given the numerical value of c. For example, if you were told that c equals 1, you would substitute 1 for c and get:
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Subtracting the two terms on the right side will result in an answer of  which simplifies to 1. So when c equals 1 you can say that x also equals 1.
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Hope this helps you to understand the problem.
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