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SAT Math: Algebra

Roots and Radicals

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A.  7
B.  13
C.  49
D.  91
E.  364

Knowsys Method

Read the problem carefully.  Note that an integer is a whole number, not a fraction.

Identify the bottom line.  Least potential value of x = ?

Assess your options.  You could plug in each of the answer choices and find the smallest choice that results in an integer, but there is a much quicker way to solve this type of problem.

Attack the problem.

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Loop back.  Did you solve for the bottom line? Yes.  

The correct answer is D.
This is a medium-level problem.

 

Want some help reviewing the math concepts you need to master?  Try out the Knowsys Pre-Algebra Flashcards, the Knowsys Algebra I Flashcards, and the Knowsys SAT & ACT Math Practice book.  

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