Help on a quiz problem.?

This is an absolute value problem. This can b rephrased as: 3x + 4 = 3 + 7. Now u add 3+7=10. So now u have this: 3x + 4 = 10. Now u subtract 4 from both sides. Now u have this: 3x = 6. Finally, u divide 3 from both sides. Your final anser is: x = 2.

Got it?
 
|x| means absolute value of x - that is, without the sign. So |4| = |-4| = 4

So

3|x| + |-4| = |-3| + |7|
3|x| + 4 = 3 + 7
3|x| = 6
|x| = 2

x = -2 or 2

Note that you can't, as others have done, simplify 3|x| to 3x. This will lose a solution, as 3|x| = 3x only if x is positive.
 
Those little lines are called absolute value lines, which represent a number's absolute (or positive value.) It's just like any other equation, but it will help you later in the solution.

3x+4=-3+7

First, simplify your problem.
Since you have absolute value signs, your new problem is:
3x+4=3+7

Simplify it and you'll get
3x+4=10

To isolate the x, subtract 4 on both sides, which leaves you with:
3x=6

Next, divide both numbers by 3.
This leaves you with...

x=2

Check your answer and you'll find that this is the correct solution.
I hope I helped!
 
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