(65-Х)+19=52
65-Х+19=52
-x=52-19-65
-x=-32
x=32
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6+6+7+7=26 сантиметров периметр
(81+9)+(9*9)+(72/8)+(90+100)=370
1)81+9=90
2) 9*9=81
3) 72/8=9
4)100+90=109
5)90+81=171
6) 171+9=180
7) 180+171=370
∠L=180°-∠K-∠M=48°
LM=2∠K=170°
KL=2∠M=94°
KM=2∠L=96°
(2,1/3-3,3/8)×(4,4/5+2,4/9)=1,1/24×6,56/45=1630/216