4. 1)
,x ≠
2x²+7 = (x-4) * (2x-5)
2x² + 7 = 2x² - 5x - 8x + 20
7 = -5x - 8x + 20
7 = -13x + 20
13x = 20-7
13x=13
x = 1, x ≠
x = 1
2)
, x≠
3x² - 8 = (x-2) * (3x+2)
3x² - 8 = 3x² + 2x - 6x - 4
- 8 = 2x - 6x -4
-8 = -4x-4
4x = - 4 + 8
4x = 4
x = 1, x≠
x = 1