1×55=
解方程组:3(x−1)=y+55(y−1)=3(x+5)
(1)若O+O+O+口+口=55,O=口+口+口,则O=(),口=().
如图L1平行L2,角1=55°,角2=65°,求角3
解分式方程:2x2x+5−55x−2=1
有一组数依次是1,5,11,19,29,m,55,则m=()
计算:1/55+2/55+3/55+.+54/55
如图,已知∠1=20°,∠2=25°,∠A=55°,求∠BDC的度数
555 55 55 5 5 5=5555
简便计算:1/55+2/55+3/55+4/55+5/55+6/55+7/55+8/55+9/55+10/55-11/1
1/55-1/56
已知{an}是一个公差大于0的等差数列,且满足a3a6=55,a2+a7=16 (1)求数列{an}
(1/55+2/55+3/55+~+10/55)-(11/155+12/155+~20/55)