Today's soundtrack is Augury: Fragmentary Evidence, a space-themed, jazzy, technical death metal album with gorgeous artwork.
This afternoon, I'm working on the homework portion of the lesson I just did on solving quadratic equations by factoring.
I mentioned yesterday that I was going to practice using the quadratic formula based on the information I found in a video on Khan Academy. I've changed my mind. For the sake of being able to properly show my work in each of the three ways of solving quadratic equations (factoring, squaring, and using the quadratic formula), I'm going to stick with the methods that the book gives me for now.
One snag that I ran into was an equation where c was 0. How could I factor that? Google had the answer: this video on YouTube talked me through it. All it means is that the graph crosses X at 0. Fair enough. So we take the equation - in my case, 3x² + 12x = 0, then we factor what we can: we take out 3x, which gives us 3x (x + 4) = 0. So we know that 3x = 0 and x + 4 = 0. 3x/3 = 0/3; x = 0. x + 4 - 4 = 0 - 4; x = -4. So my answer is 0, -4.