1 8 Solving Equations by Subtracting Preview Warm

1 -8 Solving Equations by Subtracting Preview Warm Up California Standards Lesson Presentation Holt CA Course 1

1 -8 Solving Equations by Subtracting Warm Up Determine whether each value is a solution. 1. 86 + x = 102 for x = 16 yes 2. 18 + x = 26 for x = 4 no 3. x + 46 = 214 for x = 168 yes 4. 9 + x = 35 for x = 26 yes Holt CA Course 1

1 -8 Solving Equations by Subtracting California Standards Algebra & Functions (AF 1. 1) Write and solve one-step linear equations in one variable. Holt CA Course 1

1 -8 Solving Equations by Subtracting Objective: You will learn how to solve whole number equations by subtracting. Holt CA Course 1

1 -8 Solving Equations by Subtracting Vocabulary Inverse operations - Holt CA Course 1

1 -8 Solving Equations by Subtracting h + 14 82 h ? h + 14 h Holt CA Course 1 82 68 The equation h + 14 = 82 can be represented as a balanced scale. To find the value of h, you need h by itself on one side of a balanced scale. To get h by itself, first take away 14 from the left side of the scale. Now the scale is unbalanced. To rebalance the scale, take away 14 from the other side.

1 -8 Solving Equations by Subtracting Taking away 14 from both sides of the scale is the same as subtracting 14 from both sides of the equation. h + 14 = 82 – 14 h 0 = 68 Subtracting a number is the inverse, or opposite, of adding that number. Inverse operations are operations that undo each other or “zero” each other If an equation contains addition, solve it by subtracting from both sides to “undo” the addition. Holt CA Course 1

1 -8 Solving Equations by Subtracting Example 1: Solving Equations by Subtracting Solve the equation. Check your answer. x + 87 = 152 – 87 x 0 = 65 Check 87 is added to x. Subtract 87 from both sides to undo the addition. x + 87 = 152 65 + 87 = 152 Holt CA Course 1 Substitute 65 for x in the equation. 65 is the solution.

1 -8 Solving Equations by Subtracting Example 2: Solving Equations by Subtracting Solve the equation. Check your answer. 72 = 18 + y – 18 54 = 0 y 18 is added to y. Subtract 18 from both sides to undo the addition. Check 72 = 18 + y 72 = 18 + 54 72 = 72 Holt CA Course 1 Substitute 54 for y in the equation. 54 is the solution.

1 -8 Solving Equations by Subtracting Check It Out! Example 3 Solve the equation. Check your answer. u + 43 = 78 – 43 u 0 = 35 Check u + 43 = 78 35 + 43 = 78 78 = 78 Holt CA Course 1 43 is added to u. Subtract 43 from both sides to undo the addition. Substitute 35 for u in the equation. 35 is the solution.

1 -8 Solving Equations by Subtracting Check It Out! Example 4 Solve the equation. Check your answer. 68 = 24 + g 24 is added to g. – 24 44 = 0 Subtract 24 from both sides to undo the addition. g Check 68 = 24 + g 68 = 24 + 44 68 = 68 Holt CA Course 1 Substitute 44 for g in the equation. 44 is the solution.

1 -8 Solving Equations by Subtracting Example 5: Social Studies Application Johnstown, Cooperstown, and Springfield are located in that order in a straight line along a highway. It is 12 miles from Johnstown to Cooperstown and 95 miles from Johnstown to Springfield. Find the distance d between Cooperstown and Springfield. distance between Johnstown and Springfield 95 = distance between Johnstown and Cooperstown + = 12 + 95 = 12 + d – 12 83 = 0 d distance between Cooperstown and Springfield d 12 is added to d. Subtract 12 from both sides to undo the addition. It is 83 miles from Cooperstown to Springfield. Holt CA Course 1

1 -8 Solving Equations by Subtracting Check It Out! Example 6 Patterson, Jacobsville, and East Valley are located in that order in a straight line along a highway. It is 17 miles from Patterson to Jacobsville and 35 miles from Patterson to East Valley. Find the distance d between Jacobsville and East Valley. distance between Patterson and East Valley 35 35 = 17 + d – 17 18 = 0 d = distance between Patterson and Jacobsville + = 17 + distance between Jacobsville and East Valley 17 is added to d. Subtract 17 from both sides to undo the addition. It is 18 miles from Jacobsville to East Valley. Holt CA Course 1 d

1 -8 Solving Equations by Subtracting Procedure Holt CA Course 1

1 -8 Solving Equations by Subtracting e m o H g n i n r Lea Holt CA Course 1 On-Line Tutoring

1 -8 Solving Equations by Subtracting Lesson Quiz Solve each equation. 1. x + 15 = 72 x = 57 2. 81 = x + 24 x = 57 3. x + 22 = 67 x = 45 4. 93 = x + 14 x = 79 5. Kaitlin is 2 inches taller than Reba is 54 inches tall. How tall is Kaitlin? 56 inches Holt CA Course 1