Loading...

Lesson: Data Sufficiency Intermeddiate - 07t01

Algebra In Data Sufficiency: Equations And Unknowns

[Page 7 of 21]

When a DS algebra question stem asks the value of an unknown, read the statements to find:

  • An equation that will lead to a single value
  • Multiple equations that will allow you to solve for a single value

Do the following Data Sufficiency question, choose your answer, and then click Continue.

What is the value of x - 2y ?

Statement (1) BY ITSELF is sufficient, but statement (2) by itself is not sufficient.
Statement (2) BY ITSELF is sufficient, but statement (1) by itself is not sufficient.
Both statements TAKEN TOGETHER are sufficient, but NEITHER statement BY ITSELF is sufficient.
EACH statement BY ITSELF is sufficient.
The two statements TAKEN TOGETHER are NOT sufficient.

Countinue

Focus on the question stem. F

irst, this is a value question, which means that a statement must provide the values of each variable, or the value of the expression, to be sufficient.

Evaluate each statement separately.

Statement (1) is insufficient. Make the equation in Statement (1) look more like the question stem:

This statement does not provide enough information to answer the question. The key is that you cannot use the equation with the expression to find the value, because the latter is not an equation!

Statement (2) is sufficient. Make the equation in Statement (2) look like the question stem:

Thus, Statement (2) provides the value of .

Next to display next topic in the chapter.

Test Prep Lessons With Video Lessons and Explained MCQ