.
1. First let us complete the square:
= = = .
2. Having this, you can re-write the original equation as
= 0, or
= .
Take the square root from both sides:
x - 9 = +/-, or
x = = .
The equation is solved.
The assignment is completed.
On completing the square see the lessons
- Introduction into Quadratic Equations
- PROOF of quadratic formula by completing the square
in this site.
Also, you have this free of charge online textbook in ALGEBRA-I in this site
- ALGEBRA-I - YOUR ONLINE TEXTBOOK.
The referred lessons are the part of this textbook under the topic "Quadratic equations".