Guest Session: 1 Question Remaining.
Create Account
to save progress.
Login
Diophantine Equations
medium
0:00.0
How many positive integer pairs
(
x
,
y
)
(x, y)
(
x
,
y
)
satisfy
x
2
−
y
2
=
21
x^2 - y^2 = 21
x
2
−
y
2
=
21
?
A
1
B
2
C
3
D
4
Submit Answer