Here are the essential concepts you must grasp in order to answer the question correctly.
Absolute Value
The absolute value of a number is its distance from zero on the number line, regardless of direction. It is denoted by vertical bars, such as |x|. For example, |2| equals 2, and |-5| equals 5. Understanding absolute value is crucial for evaluating expressions that involve both positive and negative numbers.
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Substitution
Substitution is the process of replacing a variable in an expression with a specific value. In this case, we substitute x with 2 and y with -5 in the expression |x| + |y|. This technique is fundamental in algebra as it allows us to evaluate expressions and solve equations by simplifying them with known values.
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Evaluating Expressions
Evaluating an expression involves calculating its value by performing the operations indicated, using the substituted values for any variables. In the expression |x| + |y|, after substituting x and y, we compute the absolute values and then add them together. This concept is essential for finding numerical results from algebraic expressions.
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