Problem 42 Evaluate each expression if \(x=... [FREE SOLUTION]

Chapter 7: Problem 42

Evaluate each expression if $x=4$ and $y=-1.$ $$2 y$$

Short Answer

Expert verified

The value is -2.

Step by step solution

Substitute Given Values

Identify the expression that needs to be evaluated, which in this case is $2y$. Substitute the given value of $y = -1$ into the expression.

Simplification

After substitution, the expression becomes $2(-1)$. Multiply $2$ by $-1$ to simplify the expression, which results in $-2$.

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Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Substitution

Substitution is a fundamental concept in algebra that involves replacing a variable in an expression with a given value. This is particularly useful when you want to evaluate an algebraic expression under specific conditions.To perform substitution:

First, identify the variables in your expression.
Then, replace each variable with its given value.

For example, if you have the expression $2y$ and you know that $y = -1$, you will substitute $-1$ for $y$. The expression will now look like this: $2(-1)$. This step ensures that you can then move on to simplifying the numerical expression.

Simplification

After substituting values into an expression, the next step is simplification. Simplification is the process of reducing an expression to its simplest form. It involves carrying out basic arithmetic operations like addition, subtraction, multiplication, or division.For instance, with the expression $2(-1)$, you would multiply $2$ by $-1$. This operation results in $-2$. The key here is to ensure that all operations are performed correctly and according to the rules of arithmetic.

Basic Algebra

Basic algebra includes foundational skills that involve handling variables, expressions, and equations. It's crucial for solving problems and evaluating expressions.Some core principles of basic algebra include:

Understanding variables and constants.
Applying operations such as addition, subtraction, multiplication, and division.
Using algebraic expressions to represent real-world problems.

In our example, evaluating $2y$ by substituting and simplifying was straightforward because it was a simple expression. However, the principles apply to more complex expressions as well. Mastery of these basics prepares you for more advanced algebraic concepts. Understanding how to locate variables, substitute given values, and perform arithmetic operations is key.

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91影视

Evaluate each expression if \(x=4\) and \(y=-1.\) $$2 y$$

Short Answer

Step by step solution

Substitute Given Values

Simplification

Key Concepts

Substitution

Simplification

Basic Algebra

One App. One Place for Learning.

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