Blank outline for teaching factoring using diamond puzzles. Great for a warm up or to assign for homework. Teachers can fill in the numbers from a page in the book or teach students how for showing their work while factoring.
(a)x^2 + bx + c
Box on left is b and on right is c or a*c depending on level of factoring.
The two factors go on the top and bottom.
I've seen it organized differently, but I like this way because it easily can be overlaid on the original problem, helping students (and teachers) remember what goes in each box.