<span>(sin x +1)(sin x -1)=</span>sin²x-sin x+sin x+1=sin²x+1
3 тонны 8 центнер × 4 центнера 90 килограмм = 3800×490=1862000кг или 18620центнера или 1862тонны
1) P=7х+9х+10x=130
26х=130
х=5
2) а=7х=7×5=35
3) b=9x=9×5=45
4) c=10x=10×5=50
Ответ: 35; 45; 50.
1. father, mother, sister , brother, daughter, son, grandmother, grandfather.
2.1)
Becky didn`t play puzzle yesterday.
2) I'll ridwe my bike tommorow.
3)My grandma got two letters yesterday.
4) They were in the country last summer.