Question

Part A: Explain why x = 5 makes 4x - 1 5 19 true but not 4x - 1 < 19.

Answer 1

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Answer:

• 19 ≤ 19 . . . true
• 19 < 19 . . . false
• x = 9

Step-by-step explanation:

A) A number cannot be less than itself, but can be equal to itself.

In each case, the left side of the inequality evaluates to 19:

  4(5) -1 = 20 -1 = 19

It is true that 19 is less than or equal to 19. This is true because 19 = 19.

It is not true that 19 is less than 19. A number cannot be less than itself.

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B) 5x +2 = 47

  5x = 45 . . . . . . subtract 2 from both sides

  x = 9 . . . . . . . . . divide both sides by 5

The element 9 from the set is the solution to the equation.