Answer:
first option
Step-by-step explanation:
3x² - 18x + 5 = 47 ( subtract 5 from both sides )
3x² - 18x = 42 ( divide through by 3 )
x² - 6x = 14
Using the method of completing the square
add ( half the coefficient of the x- term )² to both sides
x² + 2(- 3)x + 9 = 14 + 9
(x - 3)² = 23 ( take square root of both sides )
x - 3 = ± [tex]\sqrt{23}[/tex] ( add 3 to both sides )
x = 3 ± [tex]\sqrt{23}[/tex]
