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SAT Course Online
Based on our book SAT Prep Course, this interactive, comprehensive self-study course presents the
equivalent of over 600 pages of printed material, including hundreds of SAT examples
and problems and feedback from SAT experts to your questions.
In addition, the powerful learning engine StudyDesk increases your learning
efficiency by monitoring your progress and directing you to areas where you need further study.
Also includes a copy of the SAT Prep Course book. All for only $149.95!
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Course Features:
- Ask Questions! Our instructors monitor StudyDesk to answer your questions. StudyDesk also records the step where you make a mistake or ask a question. This is just one of many powerful educational tools in StudyDesk.
- Highly Interactive: You can search the course for any topic, take notes, view solutions, view reports, and each time you return to the course it presents the last topic you were studying.
- Versatile: You can access the course from any computer at any time.
- Statistics: Your performance on the exercises and tests is saved and you may review your performance and check solutions at any time. You can also check your ranking based on all students taking the course.
- Free Book! Includes a copy of the SAT Prep Course book shipped to your home. (The course does not require the book.)
- Guarantee: If, at the end of the course, you do not feel sufficiently prepared for the test, you may repeat the course for free -- with full access to our instructors.
SAT Math - Equations Review
Click the link immediately below to view the SAT Verbal diagnostic test.
Verbal Test
EQUATIONS
In Algebra, you solve an equation for, say, y by isolating y on one side of the equality symbol. On the SAT, however, you are often asked to solve for an entire term, say, 3 - y by isolating it on one side.
Example: If a + 3a is 4 less than b + 3b, then a - b =
(A) -4 (B) -1 (C) 1/5 (D) 1/3 (E) 2
Translating the sentence into an equation gives a + 3a = b + 3b - 4
Combining like terms gives 4a = 4b - 4
Subtracting 4b from both sides gives 4a - 4b = -4
Finally, dividing by 4 gives a - b = -1
Hence, the answer is (B).
Often on the SAT, you can solve a system of two equations in two unknowns by merely adding or subtracting the equations--instead of solving for one of the variables and then substituting it into the other equation.
Example: If 4x + y = 14 and 3x + 2y = 13, then x - y =
Solution: Merely subtract the second equation from the first:
4x + y = 14
(-) 3x + 2y = 13
x - y = 1
METHOD OF SUBSTITUTION (Four-Step Method)
Although on the SAT you can usually solve a system of two equations in two unknowns by merely adding or subtracting the equations, you still need to know a standard method of solving these types of systems.
The four-step method will be illustrated with the following system:
2x + y = 10
5x - 2y = 7
1) Solve one of the equations for one of the variables:
Solving the top equation for y yields y = 10 - 2x.
2) Substitute the result in Step 1 into the other equation:
Substituting y = 10 - 2x into the bottom equation yields 5x - 2(10 - 2x) = 7.
3) Solve the resulting equation:
5x - 2(10 - 2x) = 7
5x - 20 + 4x = 7
9x - 20 = 7
9x = 27
x = 3
4) Substitute the result in Step 3 into the equation derived in Step 1:
Substituting x = 3 into y = 10 - 2x yields y = 10 - 2(3) = 10 - 6 = 4.
Hence, the solution of the system of equations is the ordered pair (3, 4).
Copyright © 2007, Nova Press
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