Download Study guide Adding/subtracting fractions

Study guide
Adding/subtracting fractions
-you need a common denominator
-only add or subtract the numerators (top number)
-remember your integer rules (same signs add them, opposite signs subtract and take the sign that you
have more of)
-when adding/subtracting mixed numbers: add/subtract the fractions first, then add/subtract the whole
numbers
-you will be able to use a calculator when adding/subtracting fractions with unlike denominators
Examples:
1/3 +2/3 = 3/3 = 1
-2/9 + -3/9= -5/9 (same signs, add them up- answer is negative because both fractions are negative)
5/7 -2/7 = 3/7
-7/13 + 2/13= -5/13 (opposite signs, subtract- answer is negative because you have more negatives)
1½+2=3½
Powers and exponents
-Base: common factor (the number that you see)
-Exponent: tells how many times the base is being multiplied
-Any number to the 0 power = 1
-Evaluating powers: write the power as a product and multiply (you will be able to use your calculator to
multiply)
-When the base has a negative power, write the base as a fraction (put 1 over it)
- Writing powers: write what you see, connecting each with a multiplication sign, and write the
exponent based on how many times you see that number
Examples (evaluating):
5³ x 3³ = 5 x 5 x 5 x 3 x 3 x 3 = 3375
2‾²=½x½=¼
Examples (writing powers):
2 x 2 x 2 x b x b = 2³ x b²
(1/2) x (1/2) x a x a x a = (1/2)² x a³