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Which values from the set {1,2,3,4} are solutions of 11>2x+5

1 Answer

3 votes

Answer: 1 and 2

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Method 1)

Solve for x

11 > 2x + 5

11-5 > 2x

6 > 2x

2x < 6

x < 6/2

x < 3

So any x value smaller than 3 will be a solution. If we only consider values from the set {1,2,3,4}, then the solution values are {1,2}

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Method 2)

Plug each value from the set {1,2,3,4} into the original inequality. If you get a true statement after simplifying, then that value is a solution. Otherwise, it is not a solution.

Let's check x = 1

11 > 2x+5

11 > 2*1+5 ... replace x with 1

11 > 2+5

11 > 7 .... true statement since 11 is larger than 7

So x = 1 is a solution

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Let's check x = 2

11 > 2x+5

11 > 2*2+5

11 > 9 .. another true statement

x = 2 is another solution

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Let's check x = 3

11 > 2x+5

11 > 2*3+5

11 > 6+5

11 > 11 .. false, no number is larger than itself

x = 3 is not a solution

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Let's check x = 4

11 > 2x+5

11 > 2*4+5

11 > 8+5

11 > 13 ... false statement

x = 4 is not a solution

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We see that only x = 1 and x = 2 are solutions.

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