ABSOLUTE VALUE
ALGEBRAIC EXPRESSIONS
49 . Negative Exponent and Rational Exponent
To find the value of a number raised to a negative exponent, simply rewrite
the number, without the negative sign, as the bottom of a fraction with 1 as
the numerator of the fraction: If x is a positive number and
a is a nonzero number, then So If p and q are
integers, then So
50 . Determining Absolute Value
The absolute value of a number is the distance of the number from zero on
the number line. Because absolute value is a distance, it is always positive.
The absolute value of 7 is 7; this is expressed |7| = 7. Similarly, the absolute
value of −7 is 7: |−7| = 7. Every positive number is the absolute value of two
numbers: itself and its negative.
51 . Evaluating an Expression
To evaluate an algebraic expression, plug in the given values for the
unknowns and calculate according to PEMDAS. To find the value of x^2 + 5x −
6 when x = −2, plug in −2 for x: (−2)^2 + 5(−2) − 6 = −12.
52 . Adding and Subtracting Monomials
