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Ch. 2 - Graphs and Functions
Lial - College Algebra 13th Edition
Lial13th EditionCollege AlgebraISBN: 9780136881063Not the one you use?Change textbook
Chapter 3, Problem 5

Fill in the blank(s) to correctly complete each sentence. For the function ƒ(x) = -4x + 2, ƒ(-2)= ______.

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Identify the given function: \(f(x) = -4x + 2\).
Substitute the input value \(x = -2\) into the function to find \(f(-2)\).
Replace \(x\) with \(-2\) in the expression: \(f(-2) = -4(-2) + 2\).
Simplify the multiplication part: calculate \(-4 \times (-2)\).
Add the result from the multiplication to 2 to find the value of \(f(-2)\).

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Key Concepts

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

Function Evaluation

Function evaluation involves substituting a given input value into the function's formula to find the corresponding output. For example, to find ƒ(-2), replace x with -2 in the expression ƒ(x) = -4x + 2 and simplify.
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Linear Functions

A linear function is a function whose graph is a straight line, typically expressed as ƒ(x) = mx + b, where m is the slope and b is the y-intercept. Understanding this form helps in quickly evaluating and interpreting the function.
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Substitution Method

The substitution method is a technique where a specific value replaces the variable in an expression or equation. This method is essential for evaluating functions at particular points, as it allows direct computation of the output.
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