Expert: Lynn Houston - 9/10/2008

Question
i dont understand this math stuff im in 8th grade...
umm here is a problom
25x+13-33X=-130

Answer
Ok, you didn't actually say what you needed to do with the equation, so I'll assume that you need to solve for x.  If that's not right, let me know.

25x   13 - 33X = -130  (first step is easy, combine the x's)
-8x   13 = -130  (now, subtract 13 from both sides of the =)
-8x   13 - 13 = -130 -13 (which is...)
-8x = -143 (now, divide both sides by -8)
-8x/-8 = -143/-8 (the 8's on the left cancel, leaving)
x = 143/8 (positive because a neg divided by a neg is positive)

It doesn't divide equally, but reduces to 17 7/8.  The secret to solving these things is to "undo" everything that has been done to the variable, so above, 13 was added, so you needed to subtract 13 from both sides.  And, just remember, whatever you do to one side, you have to do to the other.

If this doesn't make sense, let me know.