and 4 5 4 5 because positive number negative number negative number. Therefore, 4 5 can also be written as 4 5 or 4 5 b) If we divide 1 2 , we get a negative quotient, 0.5. Therefore, we can also write 1 2 as 1 2 . The negative sign in 1 2 can also be written in the denominator, since this would also give a negative quotient. 1 2 can also be written as 1 2 or 1 2 . YOU TRY 5 Write two equivalent forms of each fraction by moving its negative sign. a) 7 10 b) 3 8 ANSWERS TO YOU TRY EXERCISES 1) a) 54 b) 50 c) 32.2 2) a) 50 b) 12 c) 56 3) a) 12 b) 7 c) 4 d) 8 e) 9 f) undefi ned g) 0 4) a) 8 27 b) 1 4 5) a) 7 10 or 7 10 b) 3 8 or 3 8 . There are always three different ways to write a negative fraction. Using Technology Sometimes we have to make calculations with signed numbers following the order of operations. For example, to calculate 3.4 (6) (0.5), we must work left to right. To fi nd the value of the expression, we enter 3 . 4 6 . 5 or () 3 . 4 () 6 () . 5 ENTER into the calculator. The display screen will show 40.8 as the result. 10.4 Exercises Do the exercises, and check your work. Objective 1: Multiply Two Numbers with Different Signs 1) The product of a negative number and a number is negative. 2) The product of a positive number and a negative number is . Multiply. 3) 5 3 4) 10 4 5) 4 (8) 6) 6 (3) 7) (0)(17) 8) (30)(0) 9) (1)(38) 10) (19)(1) 11) 27(34) 12) 39(56) 13) 2 3 12 14) 5 7 21 15) 8 21 a 7 6 b 16) 25 12 4 5 17) 6.2 (5) 18) 5.5 (4) 19) 2.7(5.3) 20) 3.4(9.7) 1 2 , www.mhhe.com/messersmith SECTION 10.4 Multiplying and Dividing Signed Numbers 745
messersmith_power_basic_college_1e_ch4_7_10
To see the actual publication please follow the link above