问题 填空题
x
3
=
y
5
=
z
7
,则
x+y
y
=______,
y+3z
3y-2z
=______.
答案

根据题意,设

x
3
=
y
5
=
z
7
=k,

则x=3k,y=5k,z=7k,

x+y
y
=
3k+5k
5k
=
8
5
.
y+3z
3y-2z
=
5k+21k
15k-14k
=26,

故填

8
5
;26.

选择题
单项选择题 案例分析题