Solving One-Step Equations COURSE 3 LESSON 2-1 Solve –3 = m – 16. Since 16 is subtracted from m, you must add 16 to each side to isolate m. –3 = m – 16 –3 + 16 = m – 16 + 16 Add 16 to each side. 13 = m Simplify. –3 = –3 Subtract. –3 13 – 16 Substitute 13 for m. Check –3 = m – 16 Check the solution in the original equation. 2-1

Solving One-Step Equations COURSE 3 LESSON 2-1 After Vida adds 17 new shells to her collection, she then has a total of 52 shells. Write and solve an equation to find how many shells she had before adding the new ones. Equation s + 17 = 52 Words original number of shells plus new shells = total Let s = the original number of shells. Since 17 is added to s, you must subtract 17 from each side to isolate s. s + 17 = 52 2-1

Solving One-Step Equations COURSE 3 LESSON 2-1 (continued) s + 17 – 17 = 52 – 17 Subtract 17 from each side. s = 35 Simplify. Vida had 35 shells before adding the new ones. Check s + 17 = 52 Check the solution in the original equation. 35 + 17 52 Substitute 35 for s. 52 = 52 Add. 2-1