HP 40gs hp 40gs_user's guide_English_E_HDPMSG40E07A.pdf - Page 98

hp40g+.book Page 2 Friday, December 9, 2005 1:03 AM Define and solve the equations example in the previous step). To solve a three- equation set, press . Now the input form displays three equations. If the three-equation input form is displayed and you want to solve a two-equation set, press . In this example, we are going to solve the following equation set: 6x + 9y + 6z = 5 7x + 10y + 8z = 10 6x + 4y = 6 Hence we need the three-equation input form. 3. You define the equations you want to solve by entering the co-efficients of each variable in each equation and the constant term. Notice that the cursor is immediately positioned at the co-efficient of x in the first equation. Enter that co-efficient and press or . 4. The cursor moves to the next co-efficient. Enter that co- efficient, press or , and continue doing likewise until you have defined all the equations. Note: you can enter the name of a variable for any co-efficient or constant. Press and begin entering the name. The menu key appears. Press that key to lock alphabetic entry mode. Press it again to cancel the lock. Once you have entered enough values for the solver to be able to generate solutions, those solutions appear on the display. In the example at the right, the solver was able to find solutions for x, y, and z as soon as the first co-efficient of the last equation was entered. 8-2 Linear Solver aplet