4X-4Y=96 X的平方-Y的平方=960 求X和Y

问题描述:

4X-4Y=96 X的平方-Y的平方=960 求X和Y

已知,4X-4Y = 96 ,可得:X-Y = 24 ,
已知,X^2-Y^2 = (X+Y)(X-Y) = 960 ,可得:X+Y = 960/(X-Y) = 40 .
解方程组:X+Y = 40 ,X-Y = 24 ;
两式相加可得:2X = 64 ,解得:X = 32 ;
两式相减可得:2Y = 16 ,解得:Y = 8 .