Inequalities Section 1.5 (35)

Objectives Determine which is the greater of two numbers. Find the absolute value of a number

1.5.1 Determine Which is the Greater of Two Numbers (35) If the number is a fraction, convert the number to a decimal. Plot the two points on the number line. The number to the right is greater than ( > ) the number to the left. Similarly the number to the left is less than ( < ) the number to the right. To use the vernacular, the little one normally gets the shaft (the point).

Another Perspective First, assume the two numbers are positive and have the same whole value. Start at the decimal point, and compare each digit (tenths, hundredths, etc.). As soon as you find a difference, the larger at that position identifies the bigger. Examples: < > < 0.345

Examples Determine if the “?” should be replaced with a ? -5 ? -1 < 1/4 ? 1/6.25 ?.16> -2 ? -4 > -5.2 ? <

1.5.2 Find the Absolute Value of a Number (36) By definition, the absolute value of an expression is the distance from that value to 0 Remember distance is never negative. Absolute value is indicated by a vertical line “ | “ on either side of the expression. Examples: | 3 | = 3 | -1 | = 1 | 0 | = 0 | x | may equal x or -x depending on x

Examples Determine if the “?” should be replaced with a ? -5 ? | -6 | < | -2 | ? | -1 | > | -2 | ? 2 = | -5 | ? -5 >

Objectives Determine which is the greater of two numbers. Find the absolute value of a number

Inequalities Section 1.5 (35)