Because geometry deals with pictures, there are unique rules for geometry that can help imrove the overall math score. Here are some general rules to think about to help improve your math score on the SAT.
- Drawing - When a question describes something, it is a good idea to draw it. The picture does not have to be "art quality," but scratching it out on paper will give the test taker a good idea of what the question wants. Geometry is visual math and should be treated as such. Again, it should be stressed that the drawing does not need to be perfect as long as it helps with the final answer and getting a full point.
- Scale - If an object in a question is drawn to scale or not is very important information to have. Usually, questions are drawn to scale but occasionally they will not be so as to trick the person taking the test. If the question does not state otherwise, the figure will be drawn to scale. When figures are NOT drawn to scale, it is a good idea to only trust facts and actual numbers explicitly given in the question and not rely too much on the picture or graph.
- Fill It All In - On Geometry questions on the SAT there is occasionally a picture with no labels. These sometimes come with questions that seem difficult to solve. They will either give you a general concept that is understood but the solution or how to solve it is not known. Or there may be no comprehension about the question at all. In either case, it is a good idea to re-read the question carefully and slowly, trying to comprehend as much as possible with each and every word. A good way to help is to fill in everything that is known about a picture with a question on the SAT. Most of the time, seeing the information in visual form will help with getting the correct answer.
- Formulas - It is important to memorize as many formulas - all of them preferably - as possible. Not memorizing the formulas is a big mistake that many students make. Even if a cheat sheet is present, knowing the formula takes less time than looking it up. Also, knowing the formula can make it quicker and easier to solve problems because of the way the brain works.
SAT Formulas
Those formulas are listed at the start of every Math section on the SAT.
- The number of degrees of arc in a circle is 360.
- The measure in degrees of a straight angle is 180.
- The sum of the measure in degrees of the angles of a triangle is 180.
Perimeter vs. Area
Knowing the difference between area and perimeter is important. Perimeter is the total distance around something and is found by adding up all the sides (which isn't possible on a circle, obviously.) The area is the inside of a two dimensional shape - think square, triangle or even an octagon. The area is found by multiplying the length and width or with another formula for more complex shapes. In order to find the side of a square when the perimeter is known, it is simply a matter of dividing the permiter by four. When the area of a square is known the square root can be used to find a particular side.
Volume
There are many volume formulas, but in general - "area of the base times the height" is the most common that will be used on the SAT math section. This is applicable to all shapes - including cylinders. It is an easy way to recall the volume of any figure that may appear on the exam.
Pi π
A calculator with a PI button is needed for the SAT. It is equal to approximately 3.14. Using a calculator to get an accurate answer is recommended when dealing with this number. Make sure not to use an approximation as an answer unless the question specifically asks for it.
