Objective 22Solve one-step equations,multiply and divide ©2002 by R. Villar All Rights Reserved
Solve one-step equations, multiply and divide To “undo” multiplication, we will use division... The opposite of multiplying by –14 is dividing by –14. The –14’s will cancel leaving n by itself... –14 –14 In the last section we used addition to undo subtraction and we used subtraction to undo addition. Addition and subtraction are called inverse operations of each other. In this section we will use multiplication and division to undo each other since they are inverse operations of each other. Example: Solve 112 = –14n –8 = n 112 = –14(–8) √ Check the original problem...
Example: Solve 3 = z 9.5 28.5 = z Check: 3 = 28.5√ 9.5 To undo division, we will use multiplication... 3 • 9.5 = z • 9.5 9.5
Example: Solve Now, multiply both sides by the reciprocal of 2/3... The reciprocals will cancel leaving x on the left side... Multiply the right side to solve for x... x = – 99 16 To undo multiplication of fractions, we can use the reciprocal. We will first convert the mixed number into an improper fraction... Check: √