( -4/5)*4 - (1/25)*2+18= - 16/5 - 2/25+18= - 3 5/25 - 2/25+18= - 3 7/25+18=14 18/25
( X/2 + 5/6 )^2 = a ; a > 0
9a^2 + 14a - 8 = 0
D = 196 + 288 = 484 = 22^2
a1 = ( - 14 + 22 ) : 18 =8/18 = 4/9
a2 = ( - 14 - 22 ) : 18 = - 2 ; < 0
( X/2 + 5/6 )^2 = 4/9
X/2 + 5/6 = 2/3
6x + 5 = 4
X = - 1/6
a+5b+a²-25b²=1(a+5b)+(a-5b)(a+5b)=(a+5b)(1+a-5b)
Ответ: (a+5b)(1+a-5b)
8x+30-35x=-7x+10
8x-35x+7x=-30+10
-20x=20
x=20÷(-20)
x=-1
Ну зачем тут фото?
7.15 - 2.15 = 5
1.25 - 2.25 = -1
5/-1 = -5
8 - (-5) = 8 + 5 = 13.
Ответ: 13.