Ответ:
ответ на фото..............
Решение смотри во вложении..........................
<span>1)-38sin13/sin 347=-3sin13/sin(360-13)=-3sin13/(-sin13)=3
2)37cos171/cos9=37cos(180-9)/cos9=-37cos9/cos9=-37
3)-20tg89/tg91=-20tg(90-1)/tg(90+1) =-20ctg1/(-ctg1)=20
4)11tg167*tg225=11tg(180-13)*tg(180+45)=-11tg13*tg45=-11tg13*1=-13tg13
5)28sin68/sin292=28sin(90-22)/sin(270+22)=28cos22/(-cos22)=-28
6)28cos68/cos 112=28cos(90-22)/cos(90+22)=28sin22/(-sin22)=-28
7)4tg108/tg72=4tg(90+18)/tg(90-18)=-4ctg18/ctg18=-4
8)11sin421/sin61</span>=11sin(360+61)/sin61=11sin61/sin61=11
8-x
16-100%
800=16x
-16x=-800|:(-16)
x=50(%)
800-100%
8-x
800x=800|:800
x=1%
8000-100%
8-x
8000x=800|:8000
x=0,1%
0,8-100%
8-x
0,8x=800|:0,8
x=1000%
<span>(7x+1)-(6x-3)=5
7x+1-6x+3=5
x+4=5
x=5-4
x=1
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</span>
<span>(7*1+1)-(6*1-3)=5</span>
(7+1)-(6-3)=5
8 - 3 = 5
5 = 5