现在有螃蟹、蜻蜓、螳螂,共35只.合计有腿238只,翅膀50对.
1个回答

螃蟹=a,蜻蜓=b,螳螂=c

1)10a+6b+6c=238

2)a+b+c=35

3)2b+c=50

c=50-2b -(4)

(4)to(2) a+b+50-2b=35

b=a+15 -(5)

(5)to(4) c=50-2(a+15)

c=20-2a -(6)

(5)&(6) to (1)

10a+6(a+15)+6(20-2a)=238

4a=28

a=7 -(7)

from (7),(5)&(6)

b=7+15=22

c=20-2(7)=6

螃蟹=7,蜻蜓=22,螳螂=6