Answer: 8.8
Explanation:
The x term 6x has coefficient 6.
Cut that coefficient in half to get 3.
Then square the 3 to get 3^2 = 9.
We need to add 9 to both sides to complete the square.
So we'd have these steps
[tex]x^2+6x = 130\\\\
x^2+6x+9 = 130+9\\\\
(x+3)^2 = 139\\\\
x+3 = \sqrt{139} \ \ \text{ focusing on the positive root only}\\\\
x = -3+\sqrt{139}\\\\
x \approx 8.789826\\\\
x \approx 8.8\\\\[/tex]
