二元一次方程解题

因为解相同，所以2x+5y=-6和3x-5y=16 联立 得x=2，y=-2
mx-ny=-4和nx+my=-8联立，代入 x=2，y=-2得，m=2，n=-3
所以(2m+n)=1，2005次方=1

solve the equation set of
{2x+5y=-6
{3x-5y=16
use the answer to replace the x,y of the equation set
{mx-ny=-4
{nx+my=-8
then solve this equation, you can get the value of m,n
then the value of (2m+n)^2005 can be calculated

自己想

x=2,y=-2,n=-3,m=1
2m+n=-1所以2005次方为-1