Math Arguments
Problems, Questions, and Puzzles to spark discussion and argument in the maths classroom.
Complete The Square
What do you think of this method of completing the square?
Prof Butler likes it because you can go direct from factored form to vertex form.
\( x^2 + 12x + 35 \)
\( = x(x + 12) + 35 \)
\( = (x + 6 - 6)(x + 6 + 6) + 35 \)
\( = (x + 6)^2 - 36 + 35 \)
\( = (x + 6)^2 - 1 \)
How does the special factoring of \(a^2 - b^2 \) come into all of this?
.
Source:
David Butler
Rather fond of this method of completing the square, especially because you can use it to go direct from factored form to vertex form.
— David Butler (@DavidKButlerUoA) November 3, 2019
More Information:
++