Datasheet

288
S
S
o
o
l
l
v
v
i
i
n
n
g
g
s
s
i
i
m
m
u
u
l
l
t
t
a
a
n
n
e
e
o
o
u
u
s
s
e
e
q
q
u
u
a
a
t
t
i
i
o
o
n
n
s
s
.
.
Solve the systems of equations below:
(i)
23 7
42
xy
xy
−=−


+=

(ii)
24
3 2 10.5
3 10.5
xy
xyz
xyz
−
=
−+ −=−
−+=
Method 1 - Graphing the lines
Because the first set of equations is a 2x2
system it can be graphed in the Function aplet.
To do this it is necessary to re-arrange the
functions into the form y = …… and store
them into F1(X) and F2(X) in the SYMB view
of the Function aplet. Switch to the PLOT view
and use the Intersection tool to find
the point of intersection.
It is worth noting that although the point of intersection is on the screen here,
this is not necessary. The Intersection tool will work even if
neither line is visible on the currently set axes.
Second method - using a matrix
Step 1. Rewrite
23 7
42
xy
xy
−=−


+=

as
23 7
14 2
x
y
−
−

   
=

   

   
This means that
1
23 7
14 2
x
y
−
−
−
    
=×
    
    
Step 2. Switch into the Matrix Catalog (SHIFT
MATRIX). Position the highlight on M1
and press
. Enter the matrix
shown right.
Press SHIFT MATRIX to change
back to the catalog and create M2 as
shown below right. Note that setting
will make it easier to enter M2.