On this worksheet we will investigate how addition and subtraction of a constant will affect an inequality. The sketch below shows a number line with the numbers A and B marked. You can add the same number to both A and B by dragging the slider, point P.
1. In starting position, which is larger, A or B? Fill in the first line of the table below. Use the inequality symbols < and >. 2. Drag point P to add 2 to both numbers. Now which is larger, A+P or B+P? Fill in the second line of the table. 3. How can you use the slider to subtract the same number from both A and B? Subtract 3 and fill in the third line of the table. 4. Fill in the rest of the Table Operation........................Position of A+P...............Inequality symbol...............Position of B+P Starting number.........................1........................................???....................................2 Add 2 Subtract 3 Add −2 Subtract −4 What happens to the relative position of numbers A+P and B+P when you add or subtract a positive number? A negative number? Does anything happen to the direction of the inequality symbol?