Question

鸡兔同笼,有17个头,42条腿,鸡兔各有几只?4x+（17﹣x）=42

Answer 1

设兔x只,鸡17-x只

则4x+2(17-x)=42

4x+34-2x=42

2x=8

x=4

17-x=13

所以兔4只,鸡13只