ah yeah, I didn't notice the brackets
if you have an absolute value equation with absolute values on both sides, as in
|x+1| = 9|3-x|
In a video, the guy made both positive and then one negative and one positive. He didn't explain why, but from playing around with random equations, I'm guessing it's to find all cases - making both negative will always give positive right?
I'm not too comfortable with absolute values, is this covered in-depth in VCE math? or is it yr 8/9/10 math?
and when you have a complex fraction (i believe that's what i saw them being referred to as), such as [(1/3) + (1/9)]/3, why must you separate the fractions before flipping them?
i.e. you can't say it's equivalent to (1/3)/(3+9),
i know you have to to get the right answer but i can't yet deduce the reason why