求X Y整数解

问题描述:

求X Y整数解
x^2-8x+y^2+4y=5 ,(x,y)有多少个整数解?

(x-4)^2+(y+2)^2=25 即 A^2+B^2=25
又因为均为整数,所以
1.|A|=0 |B|=5
2.|A|=3 |B|=4
3.|A|=4 |B|=3
4.|A|=5 |B|=0
(4,3) (4,-7) (7,2) (7,-6) (1,2) (1,-6) (0,1) (0,-5) (8,1) (8,-5) (9,-2) (9,-2)
12个