问题
填空题
已知
|
答案
设
=x 3
=y 4
=t,z 5
则x=3t,y=4t,z=5t,
代入4x-5y+2z=10中,得
12t-20t+10t=10,
解得t=5,
∴2x-5y+z=6t-20t+5t,
=-9t,
=-45.
故本题答案为:-45.
已知
|
设
=x 3
=y 4
=t,z 5
则x=3t,y=4t,z=5t,
代入4x-5y+2z=10中,得
12t-20t+10t=10,
解得t=5,
∴2x-5y+z=6t-20t+5t,
=-9t,
=-45.
故本题答案为:-45.