On the most advanced GMAT content, you will see complicated geometric figures. While these questions are often the most daunting questions, you (as the prepared and confident test taker) will realize that the GMAT is only testing a couple concepts.
The geometric concepts you need to know on test day include the equations for finding the area, circumference, and volume of triangles, circles, and quadrilaterals. That is it. Nothing else. While those are straight forward topics, Multiple Figures on the GMAT push your understanding of these concepts to the extreme.
When presented with a complex image that doesn’t easily fit into the category of circle, triangle, or quadrilateral, you want to proceed by following the check list below to identify the relevant component of the image that will unlock the simplicity mentioned above:
Are there parallel lines?
This may be one of the most helpful questions you can ask. If there are parallel lines, you can deduce a significant amount of information from the properties of parallel lines and the subsequent angles of the intersecting lines.
Are there recognizable angles?
As you are studying for the GMAT, you will come across several common triangles that conform to common, simplistic structure, including 30-60-90 degree triangles and 45- 45- 90 triangles. These angles have important properties that can unlock the right answer.
If it is circle, can I figure out the radius or diameter?
Of course, if you can calculate either the radius or the diameter, you can calculate the other. However, for any image containing a circle, the radius is the key to solving the problem. Identify creative ways of locating it.
Do I know the internal angles?
The internal angles of triangles sum to 180. The internal angles of quadrilaterals sum to 360. Can you backsolve with these totals into the correct answer?
Consider the above four points a simple checklist to approach the most difficult GMAT geometry content. Many times, you’ll be required to employ several of the points above to uncover the right answer. These represent just the points you want to start evaluating.
Remember, you have to memorize certain formulas and be able to apply them to complex situations. The combination of memorization and strategy together is the key to a fantastic score. Good luck on geometry!