## Jadedry one year ago Hi! I'm having trouble with the following question: "Solve the following quadratic formula by completing the square: x^2 -2x +a = 0 " So far, I'm managed to find out that a)The equation has 2 distinct roots because "b^2 -4ac" = positive b) One of the roots is 1. My textbook says that the other answer is sqrt(1-a) but I can't get that answer. My calculations show that the answer should be (sqrt(1-a) + 1 ) Could you please show working? Thanks in advance!

1. hartnn

so you know how to solve quadratics using completing the square method... can you just post first few steps of your working??

2. hartnn

i believe you reached till $$\large x^2 -2x+1 = 1-a$$ right ??

3. hartnn

oh and just so you know, your answer of $$\large x = \sqrt{1-a}+ 1$$ is correct. and the book is wrong

4. hartnn

another answer is $$\large x = -\sqrt{1-a} +1$$

I did indeed reach $x^{2}-2x +1 = 1-a$ at which point it seemed that $x-1 = \sqrt{1-a}$ -- Glad to know that my answer was right though! I was ripping my hair out. Thanks for clarifying. c:

6. hartnn

welcome ^_^ i see you're new here, $$\Huge \mathcal{\text{Welcome To OpenStudy}\ddot\smile}$$