Problem 114 of 7
Fill the blank in this quadratic-formula derivation: x+b/(2a)=±sqrt(b^2-4ac)/(2a), so x= -b/(2a) ____.
Using a hint is okay. It just tells the trainer to give you a little more review.
Hidden until you reveal it.
track algebraic transformations.
Hidden until you reveal it.
Blank must be one algebraic expression from the standard derivation.
Enter your answer
Your answer is equivalent to the expected form.
Walkthrough
Full solution stays hidden until you ask for it.
1. Identify which derivation stage the blank belongs to.
2. Use completing-square algebra to fill the equivalent expression.
3. Check denominators and signs before finalizing.
Use the worked steps, then substitute the final answer back into the original relationship to confirm it satisfies the prompt.
Missing plus/minus on square-root steps.