S12=64+(12-1)*(-3) *6= 31*6=186
X=12-y
(12-y)*y=35
x=12-y
12y-y²=35
x=12-y
y²-12y+35=0
D=144-140=4
y1= (12-2)/2= 5
y2= (12+2)/2= 7
x1= 7
x2= 5
Ответ: (7;5), (5;7)
2 пятых минус 0.7 = 0.4-0.7 = - 0.3
1. ab+b-a-1 2.x-3-xy-3y 3.cx-8c 4.x-p+p-cx
X^2-12x+20=x^2-2x
-10x+20=0
-10x=-20
x=(-20)/(-10)
<span>x=2 </span>