已知x:y:z=4:5:7,求3x-2y+z⼀2x+3y+z的值

2025-04-29 19:38:53
推荐回答(1个)
回答1:

x:y:z=4:5:7设x=4t y=5t z=7t3x-2y+z/2x+3y+z=12t-10t+7t/8t+15t+7t=9t/30t=3/10