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Example

Evaluating 7x−47x - 4 for Given Values of xx

To evaluate the expression 7x−47x - 4:

When x=5x = 5: Replace xx with 5{5} to obtain 7(5)−47(5) - 4. Multiply first: 7⋅5=357 \cdot 5 = 35. Then subtract: 35−4=3135 - 4 = 31.

When x=1x = 1: Replace xx with 1{1} to obtain 7(1)−47(1) - 4. Multiply first: 7⋅1=77 \cdot 1 = 7. Then subtract: 7−4=37 - 4 = 3.

Notice that the same expression produces different numerical results depending on which value is substituted for the variable.

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Updated 2026-04-21

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