McGraw Hill Glencoe Algebra 1, 2012
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McGraw Hill Glencoe Algebra 1, 2012 View details
3. Solving Multi-Step Inequalities
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Exercise 23 Page 301

The phrase at least can be translated to ≥.

Example Variable: Let x represent the number.
Inequality: 2/3x+6 ≥ 22
Solution Set: {x | x≥24 }

Practice makes perfect

To algebraically express a verbal inequality, we will need to translate the given information into mathematical symbols and operations.

Writing the Inequality

The phrase is at least can be expressed as ≥. This symbol will be in the middle of our expression.d ... ≥... On the left-hand side of the inequality symbol, we will translate any verbal expression that comes before is at least. If we let x represent a number, we can form an algebraic expression. Note that x is an example variable — we can use any letter to represent it.

Two thirds of a number added to six 2/3 x + 6 On the right-hand side of the inequality symbol, we will translate any verbal expression that comes after is at least. twenty-two 22 Finally, we can bring these two expressions together to form the inequality. 2/3x+6≥ 22

Solving the Inequality

Using the Properties of Inequality, we will solve the inequality by isolating the variable.
2/3x+6 ≥ 22
2/3x ≥ 16
2x ≥ 48
x ≥ 24
This solution tells us that all values greater than or equal to 24 satisfy the inequality. Let's write the solution set. {x | x≥ 24}

Checking Our Solution

We can check our solution by substituting a few arbitrary values into the inequality translated in the previous part. The value satisfies the inequality if the inequality remains true after substituting and simplifying.

x 2/3x+6 ≥ 22 Evaluate
21 2/3 ( 21)+6 ? ≥ 22 20 ≱ 22
24 2/3( 24)+6 ? ≥ 22 22 ≥ 22
27 2/3( 27)+6 ? ≥ 22 24≥ 22

We can conclude that, as long as x is greater than or equal to 24, the inequality is satisfied. This means the solution set we have found is correct.