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Chapter 1 - XYZ Custom Plus

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18<strong>Chapter</strong> 1 The BasicsProperty 1Multiplying the numerator and denominator of a fraction by the samenonzero number never changes the value of the fraction.Property 2Dividing the numerator and denominator of a fraction by the same nonzeronumber never changes the value of the fraction.2. Write ​_ 5 ​as an equivalent fractionwith denominator848.Example 2Write ​_3 ​as an equivalent fraction with denominator 20.4Solution The denominator of the original fraction is 4. The fraction we are tryingto find must have a denominator of 20. We know that if we multiply 4 by 5, weget 20. Property 1 indicates that we are free to multiply the denominator by 5 aslong as we do the same to the numerator._​ 3 4 ​= ​3 _ ⋅ 5 ​= ​15_4 ⋅ 5 20 ​The fraction ​_1520 ​is equivalent to the fraction ​3 _4 ​.C Absolute ValuesRepresenting numbers on the number line lets us give each number two importantproperties: a direction from zero and a distance from zero. The directionfrom zero is represented by the sign in front of the number. (A number without asign is understood to be positive.) The distance from zero is called the absolutevalue of the number, as the following definition indicates.DefinitionThe absolute value of a real number is its distance from zero on thenumber line. If x represents a real number, then the absolute value of x iswritten ​| x |​.Write each expression withoutabsolute value bars.3. ​| 7 |​Example 3Write the expression ​| 5 |​without absolute value bars.Solution ​| 5 |​ = 5 The number 5 is 5 units from zero4. ​| −7 |​5. ​| − ​3 _4 ​ | ​Answers2. ​ 30 _48 ​ 3. 7 4. 7 5. ​3 _4 ​Example 4Write the expression ​| −5 |​without absolute value bars.Solution ​| −5 |​ = 5 The number −5 is 5 units from zeroExample 5Write the expression ​| − ​1 _2 | ​ ​without absolute value bars.Solution​| − ​1 _2 ​ | ​ = ​1 _2 ​ The number − ​1 _2 ​ is ​1 _​ unit from zero2The absolute value of a number is never negative. It is the distance the numberis from zero without regard to which direction it is from zero. When workingwith the absolute value of sums and differences, we must simplify the expression

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