If |4X – 7| = 5 then the values of 2 |X| - | - X| is:
1/2, 3
The problem asks us to first solve an absolute value equation to find the possible values of X, and then substitute these values into a given expression to find its corresponding numerical results. The core concepts involved are understanding absolute value and simplifying algebraic expressions.
An absolute value equation of the form $|A| = B$ means that $A$ can be either $B$ or $-B$. In this problem, $A = 4X - 7$ and $B = 5$. Therefore, we will have two separate cases to solve for X:
To solve for X, we will isolate X on one side of the equation:
Similarly, we isolate X for this case:
So, the possible values for X are $3$ and $\frac{1}{2}$.
Now that we have the values of X, we need to calculate the value of the expression $2 |X| - | - X|$ for each of these X values.
First, let's simplify the expression. Remember a key property of absolute values: $|-a| = |a|$. Using this property, we can simplify $|-X|$ to $|X|$.
The expression becomes:
$2 |X| - |X|$
By combining like terms, we get:
$|X|$
So, for each value of X, the value of the expression $2 |X| - | - X|$ is simply $|X|$.
When $X = 3$, we substitute this value into the simplified expression:
$|X| = |3| = 3$
When $X = \frac{1}{2}$, we substitute this value into the simplified expression:
$|X| = |\frac{1}{2}| = \frac{1}{2}$
Based on our calculations, the values of $2 |X| - | - X|$ corresponding to the two possible values of X are $3$ and $\frac{1}{2}$.
The solution values are $\frac{1}{2}$ and $3$.
We can summarize the results in a table:
| Original Equation Result for X | Expression Value ($2 |X| - | - X| = |X|$) |
|---|---|
| $X = 3$ | $3$ |
| $X = \frac{1}{2}$ | $\frac{1}{2}$ |
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