Question

已知(x-y+z)/y=(y-x+z)/x=(x+y-z)/z=k,求k的值

Answer 1

(x-y+z)/y=(y-x+z)/x=(x+y-z)/z=k

x-y+z=yk

y-x+z=xk

x+y-z=zk

三式相加得

x+y+z=(x+y+z)k

k=1

第二题周长是102cm