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Ch. P - Fundamental Concepts of Algebra
Blitzer - College Algebra 8th Edition
Blitzer8th EditionCollege AlgebraISBN: 9780136970514Not the one you use?Change textbook
Chapter 1, Problem 11

In Exercises 1–16, evaluate each algebraic expression for the given value or values of the variable(s). x2-3(x-y), for x=8 and y=2

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Step 1: Start by substituting the given values of the variables into the algebraic expression. Replace x with 8 and y with 2 in the expression x^2 - 3(x - y).
Step 2: Rewrite the expression after substitution: (8)^2 - 3(8 - 2).
Step 3: Simplify the exponentiation first. Calculate 8^2, which means multiplying 8 by itself.
Step 4: Simplify the parentheses next. Subtract 2 from 8 to evaluate (8 - 2).
Step 5: Multiply the result of (8 - 2) by -3, then combine it with the result of 8^2 to simplify the entire expression.

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Algebraic Expressions

An algebraic expression is a mathematical phrase that can include numbers, variables, and operation symbols. In this case, the expression x^2 - 3(x - y) combines these elements to represent a value based on the variables x and y. Understanding how to manipulate and evaluate these expressions is fundamental in algebra.
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Substitution

Substitution is the process of replacing variables in an expression with their corresponding numerical values. For the given expression, substituting x = 8 and y = 2 means replacing x and y in the expression to simplify and calculate the result. This technique is essential for evaluating algebraic expressions accurately.
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Order of Operations

The order of operations is a set of rules that dictates the sequence in which different operations should be performed in a mathematical expression. Commonly remembered by the acronym PEMDAS (Parentheses, Exponents, Multiplication and Division, Addition and Subtraction), following this order ensures that calculations are performed correctly and consistently.
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