Help me what the difference between solving this |2b + 9|, why this one requiers simple and this one......?

Question

Like for this one |x+3| = 4 they split it up into two equation negative and positive...btw i still dont no how or why they do that


and in this one |2b+9| some one just solved for b i mean

help how do i solve

im not asking what absolute vcalue is but how i solve those and why were there two differnce ways to solve

Answer 1

The || signs represent absolute value. This is a term that means the distance of a number on a number line to zero. Absolute value is thus always positive. For example, |2| = 2 and |-2| = 2.

For equations where you are solving for a variable and one side is absolute value, you must solve the variable so it can equal both the negative and positive values. Using the example above, this means we have to set the equation so that x+3 equals both 4 and -4. This is because regardless of the negative or positive part, it will change into 4 because it is absolute value. Here is how you do it:
|x+3| = 4
x+3=4
x=1
Thats the normal way, as if there were no absolute value marks.
But we have to account for the negative part too:
x+3=-4
x=-7

Now to prove this is true:
|x+3|=4
|(1)+3|=4
|4|=4
The negative too:
|(-7)+3|=4
|-4|=4

I don't know how the second equation would work, partially because I don't know the full equation. Perhaps you meant |2b+9|=0 ? Otherwise, you can't do anything further. I hope I explained it well.

Answer 2

|x| means "the absolute value of x." Whether x is positive or negative, the absolute value of x is always positive.

Therefore, if |x| = 2, then x can equal +2 or -2.

For the problem you gave above, x+3 can equal 4 or -4. That is why you have to solve two problems:

1) x+3 = 4 (x=1)

2) x+3 = -4 (x= -7)

Answer 3

|x + 3| = 4
x + 3 = ±4
x = -7 or 1

Just keep in mind, you can't have an absolute value of a negative number.

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|2b + 9| = 4
2b + 9 = ±4
2b = -13 or -5
b = (-13/2) or (-5/2)

since i don't know what you want this to equal to.

Answer 4

they work one as a negative (-) problem and one as a positive (+) problem to prove a point. Even though one answer is negative when it is placed inside of those bars it automatically becomes positive.

Answer 5

it is the absolte value , because anything inside the bars, even if it is negative, will always be positive.