1. Figure 2.1a Evaluating Expressions To evaluate an algebraic expression, we may substitute the value(s) in place of the variable(s) and evaluate the numeric expression. Be sure to enclose the values substituted in parentheses. For Figure 2.1a, )( ))( () ) () (( 5214 2143 x2x2 x2x2 - - (-) ENTER Technology 2.1 1 of 3

2. Evaluating Expressions Figure 2.1b To evaluate an algebraic expression, we may store the value for the variables and enter the algebraic expression. For ease in reading, we will enter all of these commands as one entry. To do so, we separate each entry with a colon,. Store the three values for a, b, and c separated by colons. For Figure 2.1b, ALPHA : 2 B3A C 1 :: : ► ► ► Technology 2.1 2 of 3 Enter the expression. ALPHA Bx2x2 -4 AC ENTER

3. Evaluating Expressions In order to enter the second expression without retyping, recall the previous entry and edit it. Press to recall the previous entry. Then edit the previous entry, using the arrow keys in combination with delete,, and insert. 2nd ENTRY DEL 2nd INS Move the cursor to the left, using the arrow keys. Place the cursor on top of the 3 and delete 3,. Insert the new value for b, -5, ENTRY 2nd DEL 2nd INS (-)5 ENTER Technology 2.1 3 of 3 Figure 2.1b

4. Testing Algebraic Equations Determine whether x = 5 is a solution of the equation 4x - 3 = 3x + 2. Figure 2.2a Check the value given by evaluating the expression on the left and the expression on the right. Store the given value for the variable, x = 5. For Figure 2.2a, 5 ► ALPHA : Enter the right side and the left side separately. 3 4 + - 2 3 ENTER Since 17 = 17, x = 5 is a solution. Technology 2.2 X,T, ,n Separate the entries. 1 of 2

5. Testing Algebraic Equations Determine whether x = 5 is a solution of the equation 4x - 3 = 3x + 2. Figure 2.2b For Figure 2.2b, Check the value by using the TEST function of the calculator. Store the given value for the variable, x = 5. 5 ► Separate the entries. ALPHA : Enter the the equation. The equals sign is under TEST menu option 1. 23134 ENTERTEST 2nd+- The calculator returns a 1 to indicate that the equation is true and returns a 0 to indicate that the equation is false. Since the calculator returned a 1, x = 5 is a solution of the equation. Technology 2.2 X,T, ,n 2 of 2