8х + 16 = 0,
8х = -16,
х = -16 : 8,
х = -2,
3х - 21 ≤ 0,
3х ≤ 21,
х ≤ 7,
8х² - 12х + 1 = 0,
Д = (-12)² - 4*8*1 = 144 - 32 = 112,
х1 = (12 + 4√7) / 2*8 = (3 + √7)/4,
х2 = (12 - 4√7) / 2*8 = (3 - √7)/4,
(3,05 - 2,125 * 3,2) : 5/6 + 1 1/6 =
= (3,05 - 6,8) * 6/5 + 1 1/6 =
= -3,75 * 6/5 + 1 1/6 =
= -375/100 * 6/5 + 1 1/6 =
= -9/2 + 7/6 = -27/6 + 7/6 = -20/6 = -3 1/3,
(а²+10а+25)/(а²-25) =
= (а+5)²/(а-5)(а+5) = (а + 5)/(а - 5),
(в + 5)² = в² + 10в + 25,
36ву - 9су = 9у * (4в - с),
(64в⁻⁶)⁻¹⁾⁶ = 64⁻⁶°⁽⁻¹⁾⁶⁾ = 64¹ = 64
А.
x+3*25=87;
x + 75 = 87
x = 87 - 75
x = 12
О.
8*17-x=107;
136 - x = 107
x = 136 - 107
x = 29
К.
555:5-x=74;
111 - x = 74
x = 111 - 74
x = 37
П.
2x+87=93;
2x = 93 - 67
2x = 26
x = 26 : 2
x = 13
М.
3*(35-x)=63
35 - x = 63 : 3
35 - x = 21
x = 35 - 21
x = 14
С.
(120-x):13=8
120 - x = 8 * 13
120 - x = 104
x = 120 - 104
x = 16