If you want to do well on a geometry test, it's helpful to spend ten or fifteen minutes re-learning the key ideas each day before moving on to homework practice problems. Repetition is key, and understanding the basics will allow you to work on more difficult problems that require deeper thinking skills.

Today we're reviewing points, lines and planes. A point is a single location in space that does not have a length, width or height. You can describe a point using its co-ordinates, which are the coordinates of other points with which it has a relationship. You can also use a point as a reference in a line, circle or plane.

Lines are straight lines that intersect to form two angles. There are three types of angles: acute, right and obtuse. The SAT tests you on angles, so it's important to understand all three of them.

Planes are two-dimensional shapes such as squares, triangles, rhombi, rectangles and parallelograms. You'll find an interactive protractor on this page to help you see how each of these shapes is formed. Then, read about the properties of these shapes and do the review questions at the bottom of the page.

Today's review questions include a problem that asks you to use the distance formula to figure out the difference between two points. This type of question is often one of the more difficult on a geometry test, so it's a good idea to give it some extra attention before you move on to the other reviews.