offers hundreds of practice questions and video explanations. Go there now.

# Archive | Algebra

## GMAT Math: How to Divide by a Square Root

A lot of students prepping for GMAT Quant, especially those GMAT students away from math for a long time, get lost when trying to divide by a square root. However, dividing by square roots is not something that should intimidate you. With a short refresher course, you’ll be able to divide by square roots in […]

## Challenging GMAT Math Practice Questions

Here are fifteen challenging questions for GMAT math practice with explanations. Can you keep the GMAT Quant pace, doing these in under 90 seconds each?

Muitos estudantes de GMAT ficam perdidos tentando dividir raízes quadradas. Mike mostra como resolvê-las!

Muchos estudiantes del GMAT se pierden al tratar de dividir por una raíz cuadrada. ¡Mike te enseña cómo resolverlo!

## Algebraic Fractions on the GMAT

More formally, these are called “rational expressions” in mathematics — “rational” in the sense of “having do with a ratio”, as the word is used in the phrase “rational numbers“.   These rational expression appear in some of the most challenging Quant problems on the GMAT.   Here are a few practice questions. (A) –2 (B) –1 […]

## GMAT Quant: Three Equations, Three Unknowns

First, here are two challenging Quant problems, both involving three equations with three algebraic unknowns. 2a + b + 3c = 6 a – b + 5c = 12 3a + 2b + 2c = 2 1) Given the equations above, what does the product a*b*c equal? (A) 6 (B) -6 (C) 12 (D) -12 […]

## GMAT Math: Strange Symbols

The GMAT sometimes features quant questions with strange symbols. These symbols should not fluster you too much as long as you remember that they do not represent standard mathematical notation. Instead, the symbols pertain only to the problem and are defined by the GMAT (or whatever prep material you happen to be using). Let’s have […]

## GMAT Math: Algebra Equations with Radicals

This is a potentially tricky topic.  First, consider these practice questions. 1. Which value(s) of x satisfies the equation above? I. –1 II. 4 III. 9 (A) I   (B) III   (C) I & II   (D) I & III   (E) I, II, & III 2. What is the value of y? A […]

## Three Algebra Formulas Essential for the GMAT

First, a few practice problems. 1) The numbers a, b, and c are all positive.  If , then what is the value of ? Statement #1: a – b = 3 Statement #2: = 7 2) Given that (P + 2Q) is a positive number, what is the value of (P + 2Q)? Statement #1: […]

## GMAT Math: Can you divide by a variable?

Question #1: In the equation, can you divide both sides by x? Question #2: In the equation (x – 3)(x + 5) = (2x + 1)(x + 5), can you divide both sides by (x + 5)? Question #3: Question #4:   Dividing by a variable or by an algebraic expression The short answer is: […]