I think of algebra as learning to manipulate equations to find the part that is missing. An equation is any completed math problem that has the equals sign (=) in it. So, 3 x 5 = 15 would be an equation.
If you have 3 x ? = 15, algebra will tell you how to find the missing part. You just need to know what steps to take to be able to find the answer.
I think it's easy, but most people don't. I find that people generally are good at EITHER algebra or geometry. I'm good at algebra, but I cannot understand anything but the most basic geometry.
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