Приветствую!
<span>1)2x²-7x-15=0
</span>D<span> = </span>b2<span> - 4 * </span>a<span> * </span>c<span> = -7.0</span>2<span> - 4 * 2.0 * -15.0 = 169
</span>x1 = (-b + D1/2)/2a = (--7.0 + 169.01/2)/(2*2.0) = 5.0x2 = (-b - D1/2)/2a = (--7.0 - 169.01/2)/(2*2.0) = -1.5
2)<span>5x-3\3=3-10x+2\9
<span>5*x - 1 = 3 - 10*x + 2/9
х=38/135
х=0,2(814)</span></span>
14:k=14
k=14:14
k=1
9:x=3
x=9:3
x=3
a:7=56
a=56*7
a=392
5\9+1\6=5*2\18+1*3\18=10\18+3\18=13\18
5\7*14\15=5*14\7*15=2\3
10\21:5\6=10\21*6\5=2*2\7=4\7
1)36:4=9...2)9*9=81-<span>страниц в книге</span>
78*9+17=719 делимое
проверка
719/78=9(ост 17)