Fermi
·
Concept Library
·
Courses
·
Books
·
Problems
·
Simulations
·
Math Wiki
·
High School
Fermi
›
Problems
Mathematics
Mathematics
Problem
Prove that the points
(
a
,
b
)
,
(
c
,
d
)
(a, b), (c, d)
(
a
,
b
)
,
(
c
,
d
)
and
(
e
−
c
,
b
−
d
)
(e - c, b - d)
(
e
−
c
,
b
−
d
)
are collinear, if
a
d
=
b
c
ad = bc
a
d
=
b
c
.
Browse the problem library