
English: 
Hi everyone, I'll assume you have studied
my 2012 lessons
on completing the square.
If so, you saw how that method enabled us
to derive a formula
that solves any quadratic equation.
This is one formula that we do memorize because
it takes too long to derive every single time.
Let's look at this example.

English: 
Hi everyone, I'll assume you have studied
my 2012 lessons
on completing the square.
If so, you saw how that method enabled us
to derive a formula
that solves any quadratic equation.
The Quadratic Formula:
If ax² + bx + c = 0 (where a ≠ 0) has solutions,
they are given by
x = [-b ± sq rt (b² - 4ac)] / 2a.
This is one formula that we do memorize because
it takes too long to derive every single time.
Let's look at this example.

English: 
x is 
[-b ± sq rt (b² - 4ac)] / 2a.
under the square root we have 36 minus 16
Square root 20 simplies because 20 is 4 times
5.
So the answer is 3±√5
Now we have seen 2 ways of solving the same
problem.
I gave another example using the Quadratic
Formula in 2012, will add that link to the
End Screen.
Have fun!

English: 
x is 
[-b ± sq rt (b² - 4ac)] / 2a.
under the square root we have 36 minus 16
Square root 20 simplies because 20 is 4 times
5.
So the answer is 3±√5
Now we have seen 2 ways of solving the same
problem.
I gave another example using the Quadratic
Formula in 2012, will add that link to the
End Screen.
Have fun!
