550
ON A SYSTEM OF EQUATIONS CONNECTED WITH MALFATTI S PROBLEM.
[622
that is,
0 = A (EG - F'0 - F (G'H' - AF),
= K' (Aa + F'f), = K (abc +fgh) ;
which is right, in virtue of the relation K' — 0. Taking the signs all positive, we find for
(a; 2 , y 1 , z 2 , yz, zx, xy) the values (A, B, G, F', G', IF), giving two points of intersection
{^A,
and I — VA,
G'_
\lA ’ VV ’
V a ’ \/a j
Taking the signs one positive and the other two negative, say
\/BC = F', *JCA = - G', *JAB = - H',
we find for (x 2 , y 2 , z 2 , yz, zx, xy) the values
(°, T , —, F, 0, o),
viz. we have thus two intersections
(o. v't- Vf)- (°- - Vt- -'Vi
and the other combinations of signs give the remaining two pairs of intersections
;Vs- °- >Jt)- (- G Vis> °- V-
b_
GcJ ’
Aa
c
and
But the most convenient statement of the result is that the values of (ax 2 , by 2 , cz 2 , yz, zx, xy),
for the four pairs of points respectively, are
Vr- "V®- °> (Vf- - H '\Zwy °>
(a A,
bB,
cG,
F\
O',
H'),
( o ,
cG,
bB,
F,
o,
o),
(cG,
0 ,
a A,
0,
<¥,
0),
(bB,
aA,
0 ,
0,
0,
H'):
substituting
these
values in
the
verifying that the equations are in each case satisfied.