Question

He steps to derive the quadratic formula are shown below:

Answer 1

Imma translate all the steps into numbers so it's easier to see and the reason we got to that step

1. $ax^2+bx+c=0$
given

2. $ax^2+bx=-c$
minus c from both sides

3. $x^2+\frac{b}{a}=\frac{-c}{a}$
divide both sides by a

4. $x^2+\frac{bx}{a}+\frac{b^2}{4a^2}=\frac{-c}{a}$
add $\frac{b^2}{4a^2}$ to both sides, wait, we didn't add it to both sides, only the left side, MISTAKE!

so step 4 is wrong step

Answer 2

step 4 is wrong hope this helps