A graph is on a grid known as the "coordinate plane." We locate and name points on the graph as (x,y) meaning that we count x units from zero on the x-axis (going across) and y units up or down.
If you have a line drawn on a graph, find 2 places where the line goes...
Like terms are the ones that have the same variables raised to the same powers. We add or subtract like terms by adding or subtracting the coefficients, that is, the number in front. If no number is written, it is understood to be 1.
Here is your first problem, with the like terms...
Since this is a monomial (only one term), let's look at what it is made of. 3x^2 means 3 times x times x. Since these are multiplied together, they are the factors. So you would factor it as (3)(x)(x).
Hope this helps!