# Solve GRE Geometry Problem: X-Y = 30

• Spirochete
In summary, the conversation discusses a GRE geometry problem where the objective is to compare two values and determine whether one is greater, they are the same, or there is not enough information to determine. The attached MS paint version of the problem includes all measurements in degrees and is not drawn to scale. The actual answer is that (X-Y) is equal to the value 30, which is found by solving the equations 2X+2Y=180 and 2X+Y+30=180. The speaker expresses their confusion on how to solve the problem, but is grateful for the explanation.
Spirochete
I've attached an MS paint version of a GRE geometry problem. It's a quantitative comparison question. It asks you to compare two values and say whether one is greater, they're the same, or they're not enough information to say which is greater.

In the picture I drew everything is in degrees. It's not necessarily to scale.

As I've said in the picture, the actual answer is that (X-Y) is equal to the value 30. I have no clue how they figured this out though I would've said not enough information to answer.

#### Attachments

• GRE Geometry Problem.GIF
5.4 KB · Views: 430
Notice that 2X+2Y=180 and that 2X+Y+30=180.

Two equations, two unknows, solve for X and Y, then compute X-Y.

Brilliant. thank you.

## 1. What does the equation "X-Y = 30" mean in the context of a GRE geometry problem?

The equation "X-Y = 30" represents the relationship between two angles, with one angle being 30 degrees larger than the other. This is a common format for geometry problems on the GRE, where you may be asked to find the measure of one angle given the measure of another angle.

## 2. How can I use this equation to solve the geometry problem?

To solve the geometry problem, you can use algebraic techniques to manipulate the equation and solve for the values of X and Y. You may also need to use other geometry concepts, such as the properties of angles in a triangle or parallel lines, to find the missing angle measures.

## 3. Can I use a calculator to solve this problem?

No, the GRE does not allow the use of calculators on the geometry portion of the exam. You will need to use mental math and algebraic techniques to solve the problem.

## 4. Is there a specific formula or strategy I should use to solve this type of problem?

There is no one specific formula or strategy for solving geometry problems on the GRE. It is important to have a strong understanding of basic geometry concepts, as well as the ability to apply algebraic techniques to solve equations and find missing angles.

## 5. Are there any common mistakes to watch out for when solving this type of problem?

One common mistake when solving geometry problems on the GRE is to mix up the order of operations when manipulating equations. Remember to follow the rules of algebra and perform the same operation on both sides of the equation to maintain its balance. Additionally, be sure to double check your calculations and make sure you are using the correct units for angle measures (degrees or radians).

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