1
(а+5)²-(а²+25) = a²+10a+25-a²-25 = 10a.
6а-1-(а+3) = 6a-1-a-3 = 5a-4.
2
5(2-х)+10х = 52- х
10-5x+10x = 52-x
-5x+10x+x = 52-10
6x = 42
x = 7
Ответ : 7.
<span>8(3-х)-(5х+1)+3 = 13
24-8x-5x-1+3 = 13
-8x-5x = 13-24+1-3
-13x = -13
x = 1
Ответ : 1.</span>
Вот ответ надеюсь помогла
1)
<span>Применяем формулy:
arcsin
(sin х) = х - 2</span>πk
arcsin (sin 10) = 10 - 2πk
sin(пx/6)=-<span>√3/2</span>
<span>пx/6=(-1)^k+1 *п/3+пk</span>
<span>пx=(-1)^k+1 *2п+6пk</span>
<span>x=(-1)^k+1 *2п/п+6пk/п</span>
X²( x + 2) - x( x+ 1)² = 5x + 9
x³ + 2x² - x( x² + 2x + 1) = 5x+ 9
x³ + 2x² - x³ - 2x² - x = 5x + 9
- x - 5x = 9
- 6x = 9
6x = - 9
x = - 1,5