Jimmy began deriving the quadratic formula as shown.
ahhh this is a fun question but don't have time rn :( ignore all the work on the pic just start from the 1st step Ax^2+Bx+C=0 complete the square
Multiply \(\dfrac{b}{a}x\) by \(\dfrac{2}{2}\)
That should be the next step.
@Hero
I know the correct answer but I cannot tell you what it is outright.
@hero ok
@hero how can i find the answer?
One of the answer choices gives away the explanation.
But the truth is the actual next step (what I mentioned above) is not included in the answer choices.
One cannot proceed without conducting that particular step.
Subtract x² from each side?
They give you the following steps: \(ax^2 + bx + c = 0\) Divide both sides by a: \(x^2 + \dfrac{bx}{a} + \dfrac{c}{a} = 0\) Subtract \(\dfrac{c}{a}\) from both sides: \(x^2 + \dfrac{bx}{a} = -\dfrac{c}{a}\) Add \(\left(\dfrac{b}{2a}\right)^2\) to both sides: \(x^2 + \dfrac{bx}{a} + \left(\dfrac{b}{2a}\right)^2 = -\dfrac{c}{a} + \left(\dfrac{b}{2a}\right)^2\)
At this point, you're supposed to know to multiply the middle term of the left hand side by \(\dfrac{2}{2}\) to get: \(x^2 + \dfrac{2b}{2a}x + \left(\dfrac{b}{2a}\right)^2 = -\dfrac{c}{a} + \left(\dfrac{b}{2a}\right)^2\)
Thats not a choice though.
I'm not done yet
Then you would split the middle term to get: \(x^2 + \dfrac{b}{2a}x + \dfrac{b}{2a}x +\left(\dfrac{b}{2a}\right)^2 = -\dfrac{c}{a} + \left(\dfrac{b}{2a}\right)^2\) Then expand \(\left(\dfrac{b}{2a}\right)^2\) to get: \(x^2 + \dfrac{b}{2a}x + \dfrac{b}{2a}x +\dfrac{b^2}{4a^2} = -\dfrac{c}{a} + \dfrac{b}{4a^2}\)
Then: \(x\left(x + \dfrac{b}{2a}\right) + \dfrac{b}{2a}\left(x + \dfrac{b}{2a}\right) = -\dfrac{c}{a} + \dfrac{b}{4a^2}\)
And then you factor the common term on the left hand side of the equation to get: \(\left(x + \dfrac{b}{2a}\right)\left(x + \dfrac{b}{2a}\right) = -\dfrac{c}{a} + \dfrac{b}{4a^2}\) Which simplifies to \(\left(x + \dfrac{b}{2a}\right)^2 = -\dfrac{c}{a} + \dfrac{b}{4a^2}\)
All of that is the process of factoring the trinomial.
There's a typo in the steps unfortunately.
The steps are correct otherwise
hey hero, if you tell me what the error is i'll fix it ._.
On the right hand side, the last term should be \(\dfrac{b^2}{4a^2}\) everywhere you see \(\dfrac{b}{4a^2}\)
@pandasurvive are you good now?
And panda is currently AFK
No, that doesn't look right.
Don't worry about it @Ultrilliam
ok then ._.
Just try to work on the edit button. It would greatly improve the quality of my responses.
@hero thank you
You're most welcome. Anytime
Join our real-time social learning platform and learn together with your friends!