Which of the following steps should NOT be completed when evaluating the linear expression for [tex]x = 5[/tex]?

[tex]x + 5 + \frac{3x}{5} - 4[/tex]

A. Adding 5 and -4

B. Adding [tex]x[/tex] and [tex]3x[/tex]

C. Simplifying the term [tex]\frac{3x}{5}[/tex] to 3

D. Rewriting the expression as [tex]x + \frac{3x}{5} + 5 - 4[/tex]



Answer :

To determine which step should NOT be completed when evaluating the linear expression for [tex]\( x = 5 \)[/tex]:

[tex]\[ x + 5 + \frac{3x}{5} - 4 \][/tex]

Let's examine each option carefully:

A. Adding 5 and -4

Adding the constants 5 and -4 is a legitimate simplification:
[tex]\[ 5 - 4 = 1 \][/tex]
This can and should be done to simplify the expression.

B. Adding [tex]\( x \)[/tex] and [tex]\( 3x \)[/tex]

Adding like terms is valid here. Since [tex]\( x \)[/tex] and [tex]\( 3x \)[/tex] are like terms:
[tex]\[ x + 3x = 4x \][/tex]
This can and should be done to simplify the expression.

C. Simplifying the term [tex]\( \frac{3x}{5} \)[/tex] to 3

Let's check the correctness of simplifying [tex]\( \frac{3x}{5} \)[/tex] specifically for [tex]\( x = 5 \)[/tex]:

[tex]\[ \frac{3x}{5} = \frac{3 \cdot 5}{5} = \frac{15}{5} = 3 \][/tex]

This works when [tex]\( x = 5 \)[/tex], but this simplification is not generally correct for just any [tex]\( x \)[/tex]. The term [tex]\( \frac{3x}{5} \)[/tex] should remain [tex]\( \frac{3x}{5} \)[/tex] unless specifically evaluated for [tex]\( x = 5 \)[/tex]. Hence, simplifying [tex]\( \frac{3x}{5} \)[/tex] to 3 is incorrect as a general rule for the expression.

D. Rewriting the expression as [tex]\( x + \frac{3x}{5} + 5 - 4 \)[/tex]

Rewriting the expression by changing the order of terms while preserving the operations does not alter its value:
[tex]\[ x + 5 + \frac{3x}{5} - 4 \][/tex]
is equivalent to:
[tex]\[ x + \frac{3x}{5} + 5 - 4 \][/tex]

This step is legitimate and can be completed.

Given these evaluations, the step that should NOT be completed is:

[tex]\[ \boxed{C} \][/tex]

Simplifying the term [tex]\( \frac{3x}{5} \)[/tex] to 3 is not correct as a general simplification for any [tex]\( x \)[/tex], only for the specific case where [tex]\( x = 5 \)[/tex].