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HP 50g Solving linear syste ms o f equa tions using ma trices

The Nume ric Solve r
Solving linear syste ms o f equa tion s
Practice so lving linear systems

hp calculato rs
HP 50g Solving linear syste ms o f equa tions using ma trices
The Numeric So lver
The HP 50g has a nume ric so lver tha t can find the so lutions to man y diffe rent types of prob lems. It is invoked by pressing the
ORANGE shift key follo wed by the 7 key, or …Ï.
When pressed , the CHOOSE box be lo w is d isp layed:

Figure 1

The first cho ice a llo ws for the so lution o f an equation con tain ing a n umber o f unkno wns. The second cho ice solves diffe rential
equation prob lems. The th ird cho ice solve s for ze roes o f a po lynomial. The fourth cho ice to solve linear systemsof equations is the
one of in terest here . The fifth cho ice invokes the finance solve r. Th e sixth cho ice begins the mu ltiple equation solve r. To se lect the
linea r systems so lver, press 4`. The 50g d isplays the fo llowing screen:

Figure 2

There are three input areas on this fo rm. The first area is labeled A: and is where the ma trix con tain ing the coefficients of the systemof linea r equa tions are entered . The second a rea is labe led B: and is whe re the constants from the syste m o f equa tion s are ente red.
The third a rea is where the va lues o f the unkno wn va riab les X in th e syste ms o f linea r equa tion s are re turned when a so lution is
found. To ente r the coe fficients in a matrix, p ress !!!EDIT!! when the cursor is beside the area labe led A:and the MatrixWrite r is
launched.

Figure 3

In man y ways, th is screen wo rks like any spreadshee t. En ter numb ers and they will go in the h ighlighted cell. The menu labe ls a t the
lowe r left co rner of the screen , !!!GO!! and !!GO°!, dete rmine the d irection the cursor mo ves a fter a da ta po in t has been en tered , e ither
right to the next co lumn or down to the next ro w. Inth is e xamp le, th e selection is to mo ve righ t a fter each da ta po in t has been
entered. This is indica ted by the square presen t next to the !!!GO!! menu labe l. To change the way the curso r will move, press the
menu label for the d irection desired and the square in the menu lab el will change accord ingly. If a co lu mn is too small to sho w the
data ente red, the !!!WID!! and!!±WID!!! menu keys may be used to expand or sh rink the area displayed fo r each colu mn.
Ente r the first coefficien t from the first equa tion by keying in the nu mbers and pressing the `key. The curso r will move to the right
into the second co lumn where the se cond coe fficien t should be keyed with the `key pressed to accep t this va lue. At this po int,
the cursor will be in co lumn 3. Ifthe system of linear equations be in g entered has more than two un known variables, con tinue
entering the data until done . Use the ˜ and š keys to move b ack to the first co lumn and en ter the coefficien ts from the second

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HP 50g Solving linear systems of equations using matrices

hp calculato rs
HP 50g Solving linear syste ms o f equa tions using ma tricesequation . Continue en tering rows of data in to the matrix until done . If a t an y time you notice a mistake in the da ta, use the a rro w keys
to go ba ck to the incorrect data value , ke y in the co rrection , pre ss the ` key to accep t the change , and then use the arro w keys to
go back to where you were . After ente ring a matrix, the screen wou ld look some thing like th is:

Figure 4To accept the data as input, p ress the `key and the ma trix will be retu rned to the system of linear equations solve r.

Figure 5

To enter the constan ts for the linear equations, pre ss the ˜key a nd press the menu labe l !!!EDIT!! above the A key. The
MatrixW riter will be brough t up a se cond time to en ter the constan ts. Note tha t the constants are ente red as a co lumn of numbe...