1)x(y-z)-y+z=x(y-z)-(y-z)=(y-z)(x-1).
2) 2b(x-y)+y-x=2b(x-y)-(x-y)=(x-y)(2b-1).
3) 5(c-b)+ab-ac=5(c-b)-(ac-ab)=5(c-b)-a(c-b)=(c-b)(5-a).
4) 2(x-c)-bx+bc=2(x-c)-(bx-bc)=2(x-c)-b(x-c)=(x-c)(2-b).
<span> 5x-y=17 y=5x-17</span>
<span>-9x+8y=19 -9x+8(5x-17)=19 -9x+40x-136=19 31x=155 x=5 y=5*5-17=8</span>
<span>x=5 y=8</span>
<span>Tg(2°) × ctg(2°) + sin(2°) =РЕШЕНИЕ НА ФОТКЕ</span>