挑战习题
1/5单选题
难度:

1.一个笼中装有x只鸡,y只兔子,它们共有8个头,22只脚,则列出二元一次方程组是( )
A
B
C
D
提示1:
5LiA5Y+q6bih5Lik5Y+q6ISa77yb5LiA5Y+q5YWU5a2Q5Zub5Y+q6ISa
正确答案:Qg==
5YWI5YaZ5YWz57O75byP77ya4pGg6bih5pWw6YePK+WFlOaVsOmHjz0477yb4pGh6bih5pWw6YePw5cyK+WFlOaVsOmHj8OXND0yMi7iiLQ8aW1nIHdpZHRoPTEyNCBoZWlnaHQ9NTYgc3JjPSJodHRwczovL3AyLnFpbmdndW8uY29tL0cxL00wMC8zRS9GQS9yQkFDSmxUSmtxNkRDazlMQUFBRVhUY0R2TnM1MjMucG5nIj4=