Big Ideas Math Integrated I, 2016
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Big Ideas Math Integrated I, 2016 View details
6. Solving Absolute Value Inequalities
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Exercise 20 Page 91

The absolute value of the difference between the actual and normal body temperature is less than or equal to 3.

Inequality: |x-37|≤ 3
Solution: 34^(∘) to 40^(∘)

Practice makes perfect

To calculate the difference between the actual and normal body temperature of a camel, we subtract them. actual temperature- normal temperature

Writing the Inequality

We are told the normal body temperature is 37^(∘) C. Let x be the actual body temperature of a camel. x- 37

Note that the actual temperature can be lower or higher than the normal temperature. To keep the difference always non-negative, we will use absolute value. | x- 37| We also know that the body temperature of a camel varies by up to 3^(∘)C throughout a day. This means that the difference between actual and normal temperature must be less than or equal to 3^(∘)C. | x- 37| ≤ 3

Solving the Inequality

The absolute value inequality we have written before can be expressed as a compound inequality using the word and.

Absolute Value Inequality Compound Inequality
|x-37| ≤ 3 - 3 ≤ x-37
and
x-37 ≤ 3
To solve the compound inequality, we need to solve its individual inequalities one at a time. Let's start by solving - 3≤ x-37. To do so, we will use inverse operations.
- 3 ≤ x-37
34≤ x
x ≥ 34
Let's now solve x-37≤ 3.
x-37 ≤ 3
x ≤ 40
The solution to this type of compound inequality is the intersection of the solution sets. First Solution Set:& 34≤ x Second Solution Set:& x ≤ 40 Intersecting Solution Set:& 34≤ x ≤ 40 The range of actual body temperature of a camel is between 34^(∘)C and 40^(∘)C.