Assessment and Learning in Knowledge Spaces (ALEKS) Basic Math Placement Practice Test

In a two-variable equation, how can you solve for x or y?

1. By setting x or y to 1

2. By plugging in any number into x or y

3. By subtracting the constants

4. By dividing both sides by 2

The correct answer is: By plugging in any number into x or y

To solve for a variable in a two-variable equation, you can rearrange the equation using algebraic processes, and one common method is to substitute values for one of the variables. Plugging in a value for either x or y allows you to find the corresponding value of the other variable. For example, if you have an equation like y = 2x + 3, and you substitute x with a specific number, say 1, you can then solve for y: y = 2(1) + 3 = 5. This method helps you understand the relationship between the variables by providing specific instances of their values, which can be particularly useful for graphing or analyzing the equation's behavior. While there are other methods to isolate a variable by manipulating the equation, plugging in values is a straightforward approach that can yield useful results and insights into the equation's dynamics.