To do this problem, you gotta cross-multiply. SO,

multiplied by

12 times 14 = 168
21 times 3 = 63
Then the final answer is
Well to begin, you'll need a graph but you have to do:
y2-y1
---------
x2-x1
(Which is the average rate of change formula.)
In order to find your "y" you look for your x on the graph the move either direction until you touch the graph. Hope this helps.. :)
A factor table is like this chart of numbers.
For this equation you will have to substitute the y for (-x)
Therefore,
-x=3x-4
-x-3x=-4
-4x=-4
-4x/-4=-4/-4
X= 1