Question

what is \\(x + 4z - 5 - 3x\\), when \\(x = 2\\) and \\(z = 3x\\)?

a 15

b 17

c 23

d 26

Explanation:

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<reasoning>

Evaluate the variable z

\[

$$\begin{aligned} x &= 2 \\ z &= 3x = 3(2) = 6 \end{aligned}$$

\]

Substitute values into the expression

\[

$$\begin{aligned} &\text{Expression: } x + 4z - 5 - 3x \\ &= 2 + 4(6) - 5 - 3(2) \end{aligned}$$

\]

Simplify the numerical expression

\[

$$\begin{aligned} &= 2 + 24 - 5 - 6 \\ &= 26 - 5 - 6 \\ &= 21 - 6 \\ &= 15 \end{aligned}$$

\]
</reasoning>

<answer>
<mcq-correct>(A) 15</mcq-correct>
<mcq-option>(B) 17</mcq-option>
<mcq-option>(C) 23</mcq-option>
<mcq-option>(D) 26</mcq-option>
</answer>

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Answer:

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<reasoning>

Evaluate the variable z

\[

$$\begin{aligned} x &= 2 \\ z &= 3x = 3(2) = 6 \end{aligned}$$

\]

Substitute values into the expression

\[

$$\begin{aligned} &\text{Expression: } x + 4z - 5 - 3x \\ &= 2 + 4(6) - 5 - 3(2) \end{aligned}$$

\]

Simplify the numerical expression

\[

$$\begin{aligned} &= 2 + 24 - 5 - 6 \\ &= 26 - 5 - 6 \\ &= 21 - 6 \\ &= 15 \end{aligned}$$

\]
</reasoning>

<answer>
<mcq-correct>(A) 15</mcq-correct>
<mcq-option>(B) 17</mcq-option>
<mcq-option>(C) 23</mcq-option>
<mcq-option>(D) 26</mcq-option>
</answer>

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