Given the nature of the question, it's crucial to ensure clarity and context. Since the original matrix ends with a question mark, the most logical improvement would be to make it clear that the question asks for the missing value. Here's the revised format:

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Given the following matrix:

[tex]\[
\begin{array}{llll}
9 & 1 & 6 & 4 \\
4 & 5 & 7 & 2 \\
5 & 8 & 8 & 5 \\
1 & 3 & 5 & ?
\end{array}
\][/tex]

Determine the value of the question mark (?).
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This format clearly presents the matrix and states the task, making it easier to understand.



Answer :

Alright, let's solve this problem step-by-step to find the missing value in the matrix:

[tex]\[ \begin{array}{llll} 9 & 1 & 6 & 4 \\ 4 & 5 & 7 & 2 \\ 5 & 8 & 8 & 5 \\ 1 & 3 & 5 & ? \end{array} \][/tex]

### Step 1: Analyze the Given Rows

First, let's examine each row and see if there's a pattern.

#### Row 1:
[tex]\[ 9 + 1 + 6 = 16 \][/tex]
Subtracting the fourth element:
[tex]\[ 16 - 4 = 12 \][/tex]

#### Row 2:
[tex]\[ 4 + 5 + 7 = 16 \][/tex]
Subtracting the fourth element:
[tex]\[ 16 - 2 = 14 \][/tex]

#### Row 3:
[tex]\[ 5 + 8 + 8 = 21 \][/tex]
Subtracting the fourth element:
[tex]\[ 21 - 5 = 16 \][/tex]

### Step 2: Identify the Pattern

We notice that the sum of the first three elements subtracted by the fourth element does not match a consistent pattern in terms of outcome. Let's check the possible consistency within the rows themselves.

### Step 3: Perform Analysis on the Fourth Row

For the fourth row:
[tex]\[ 1 + 3 + 5 = 9 \][/tex]
We need this to meet a certain condition or consistency noted from the previous rows.

From our observations from rows 1 through 3:
- For Row 1, [tex]\( 16 - 4 = 12 \)[/tex]
- For Row 2, [tex]\( 16 - 2 = 14 \)[/tex]
- For Row 3, [tex]\( 21 - 5 = 16 \)[/tex]

A common thread appears when we check row 4. We have:
[tex]\[ 1 + 3 + 5 = 9 \][/tex]

If there was a consistent pattern, like aiming for a consistent post-subtraction result around 16, we'd need to establish continuity:
[tex]\[ 1 + 3 + 5 + ? = 16\][/tex]

Thus:
[tex]\[ 9 + ? = 16 \Rightarrow ? = 7 \][/tex]

So, the missing value in the fourth row is:
[tex]\[ \boxed{7} \][/tex]