Can standard form equation of a line have a negative A? - Answers

It's not supposed to, but that hasn't stopped teachers from teaching that it can be negative. Generally, we don't like to start equations with a negative number. That's why we say A, B, and C must be integers with A and B both not equal to zero, and A greater than or equal to zero. I've also seen Ax+By+C=0, but I disagree with that as well. The point is to solve systems and graph them easily, and having it set as Ax+By=C is probably a little better. There's no set rule. It's sort of like defining a trapezoid. Does it have to have exactly one pair of parallel lines, or can it have two pairs of parallel lines? Both of these definition are controversial. To answer your question, it's up to you. Beware, some college professors hate seeing A negative. No one will disagree with you if A is positive. It's always better to write A positive.