(2y + 3)(y + 3) = ( 2y - 1)( y - 5)
2y² + 9y + 9 = 2y² - 11y + 5
2y² - 2y² + 9y + 11y = - 9 + 5
20y = - 4
y = - 4/20
y = - 1/5
y =- 0,2
y( 5y + 1) =( y + 1)( y + 2)
5y² + y = y² + 3y + 2
5y² - y² + y - 3y - 2 = 0
4y² - 2y - 2 = 0
2y² - y - 1 = 0
D = b² - 4ac = 1 - 4×2×(-1) = 9 = 3²
x1 = ( 1 + 3) / 4 = 1
x2 = ( 1 - 3) / 4 = - 0,5
( 1 + 3x )( 1 + 2x) =( 5 - 3x)( 1 - 2x)
1 + 5x + 6x² = 5 - 13x + 6x²
6x² - 6x² + 5x + 13x = 5 - 1
18x = 4
x = 4/18
x = 2/9
( 3 - 2x)( x - 1) =( 2x - 1)( 2x + 3)
3x - 3 - 2x² + 2x = 4x² + 6x - 2x - 3
- 2x² - 4x² + 5x - 4x - 3 + 3 = 0
- 6x² + x = 0
6x² - x = 0
x( 6x - 1) = 0
Произведение равно 0.,когда один из множителей равен 0,значит,
x = 0
6x - 1 = 0
6x = 1
x = 1/6