-2/3х+4=3-1/2х
-2/3х+1/2х=3-4
-4/6х+3/6х= -1
-1/6х= -1
х= (-1):(-1/6)
х=6
<BAC= <BAD + < CD
<BAC= 32+75=107 градусов
5 7/12+1 1/3=(5+1)+(7/12+1/3)=6+7/12+4/12=6 11/12
6 3/50-3 17/75=5 53/50-3 17/75=(5-3)+(53/50-17/75)=2+159/150-34/150=2 125/150=2 5/6
5 6/55+3 9/44-4 7/22=(5+3-4)+(6/55+9/44-7/22)=4+(6*4+9*5-7*10)/220=4+(24+45-70)/220=4-1/220=3 219/220
2 1/7*2 4/5=15/7*14/5=(3*5*2*7)/(7*5)=6
2 1/16:2 5/14=33/16:33/14=33/16*14/33=14/16=7/8=0,875
3 1/6:2 1/9*1 5/9=19/6:19/9*14/9=(19*9*14)/(6*19*9)=14/6=7/3=2 1/3
1) 2*(5+3)=16 периметр прямоугольника
2) 16:4=6 сторона квадрата