来自龙艳花的问题
【若x+y+z=30,3x+y-z=50,x、y、z皆为非负数,求M=5x+4y+2z的取值范围.】
若x+y+z=30,3x+y-z=50,x、y、z皆为非负数,求M=5x+4y+2z的取值范围.
1回答
2020-03-30 08:40
【若x+y+z=30,3x+y-z=50,x、y、z皆为非负数,求M=5x+4y+2z的取值范围.】
若x+y+z=30,3x+y-z=50,x、y、z皆为非负数,求M=5x+4y+2z的取值范围.
x+y+z=30 ①3x+y−z=50 ②