What you wrote was two linear equations, but then you mentioned a vertex so you must have meant the brackets ([ and ]) to mean absolute value. Brackets have the same meaning as parentheses, so if you want to be properly understood you need to use absolute value bars. Fortunately, there is a character on your keyboard that produces absolute value bars quite nicely. Look above the Enter key (Return key on a Mac) and find the backslash button. Press Shift-Backslash and you get |.
For an absolute value function of the form :
The slope to the left of the vertex is , the slope to the right of the vertex is , and the vertex is a
Note: is the same thing as
John
My calculator said it, I believe it, that settles it
