Question

要使方程组{2x+my=16,x-2y=0}有正整数解,m可取值为___.

Answer 1

x-2y=0 ===> x=2y

2x+my=16,4y+my=(4+m)y=18

y=16/(4+m)

16=1*16=2*8=4*4

m+4=1,2,4,8,16

m=-3,-2,0,4,12