The expression (root(8 + root(63)) + (root(8 - root(63))^2 =

Hi registerincog,

Since it's been over a year since you posted, I'm not sure if you're still around to see this, but this question is more about pattern-recognition than anything else.

Bunuel has already shown how the math works, so I won't rehash that here. Instead, I'll offer some perspective.

The GMAT Quant section is going to test you on a lot of standard math rules/ideas/formulas/etc., but will sometimes test you on these rules in ways that you're not used to thinking about. When you find yourself looking at a question that is based on some "crazy-looking" numbers, then chances are really good that the question is built around a pattern of some kind (and it's a pattern that you KNOW in some other simpler format).

Here, if you ignore the numbers and square root signs, you really just have this:

(X+Y)^2

This is one of 3 Classic Quadratics that you MUST have memorized for Test Day.

(X+Y)^2 = X^2 + 2XY + Y^2

Now you can plug back in the relative values for X and Y and simplify. The "math" won't be fun, but its based on standard arithmetic rules (using radicals, multiplication, combining like terms, etc.).

GMAT assassins aren't born, they're made,
Rich

C) -> 18. Pretty straight forward.

ScottTargetTestPrep How did you get 64 - 63? Can you elaborate?

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