How To Use Your Calculator on the SAT
If you feel nervous about the math section of the SAT it can be tempting to turn to your calculator for answers. However, the test is specifically designed to make your calculator more or less useless to you. The SAT is designed to test your conceptual understanding of mathematical ideas and the application of those ideas. If the SAT was a test of your ability to approximate a calculator, they wouldn’t allow you one. So a calculator will be of very limited use to you.
There are a few cases however where using your calculator is the right move.
- Check your basic arithmetic. While you can calculate everything by hand, using a calculator for adding, subtracting, multiplying, and dividing is a good move so you don’t make a silly mistake.
- Work an example. While you should know your exponent rules (i.e. x^0 = 1) and how to graph a parabola by hand, it can be useful to double-check your understanding of how to translate a graph by using your calculator or desmos to graph an example.
- Applying the quadratic formula. There are a few problems that are difficult to solve by factoring and applying the quadratic formula is the right move. There will only be one or two occasions for this and really you should look to factor before taking this approach because factoring is faster. But in the case that you need it, applying the quadratic formula using a calculator is the way to go.
While there are some good applications for your calculator on the SAT, a calculator is not a life raft. You should focus on improving your mathematical conceptual foundations, there are only a handful to know. Here are a few to give you an idea.
- Zero product property: Anything multiplied by 0 will be 0 (i.e. 100x*0 = 0). This is a powerful concept and is the foundation for factoring quadratic equations. If two things multiplied together equal 0 that means one of them MUST be 0 (i.e. A*B = 0, which means either A or B MUST be zero and the other is any quantity with any value). Knowing this produces two equations (i.e. A=0 OR B=0). This is a simple concept but knowing how and when to apply it is the key.
- The law of equivalence: The “=” symbol is actually very different from saying two things are the same as one another. It conveys equivelence which is about the same value despite different appearances. Determining if two expressions, fractions, or equations are equivalent by manipulating appearance is a foundational skill to all of algebra. Understanding how the order of operations impacts equations (i.e. (3+7)*7 is not equivalent to 3 + (7*7)) and that doing the same thing to both sides of an equation is how you manipulate appearance without changing the value of the relationship of equivalence is on nearly every math question on the SAT.
- Constant vs Variable: A variable is like an empty box. Any value could be inside, but we don’t know yet because it varies depending on something else. Often “x” or “y” are used because of the conventions of using the xy plane and coordinate system to draw lines or graph functions. The x value changes depending on the y value. Their values are variable depending on where. you are on the line. On the other hand, a constant is a single value that is constant and does not change. We tend to use a, b, c, but can also be k or any other letter, but this is a convention. A constant can be unknown, but it is just one value. Paying attention to when a symbol/letter is described as a constant or a variable is incredibly important. Both constants and variables can be written as any letter, so it is easy to get confused if you aren’t paying attention.
If you are after a perfect score on the SAT then you must master these mathematical concepts and know how to apply them. Even for more modest goals, focusing on understanding math and not memorizing formulas is the key to improving your scores on the math section of the SAT. You can learn more about approaching math conceptually by joining one of our online courses.
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