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Substitution and value of an expression

Mathematics — first biennium · Lesson

Literal algebra

Substitution and value of an expression

Substitution means replacing every occurrence of the variable with the assigned value; with negative values parentheses protect the sign.

Rule
Formula matematica
Example
Formula matematica
What you need to know before the exercises

In this lesson: Substitute values for variables and correctly evaluate an expression.

How to proceed: Replace the letter everywhere it appears. If the value is negative, put it in parentheses before applying powers or products.

You can already assume: Algebraic expressions and rational numbers.

Try it now

Evaluate the expression for x=-4.

Guided

Completed exercises: 0/5 · Correct on first attempt: 0

How to reason

Replace the letter everywhere it appears. If the value is negative, put it in parentheses before applying powers or products.

Formula matematica

Write it as you would on paper: parentheses, signs and powers are part of the expression structure.

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What you need to know for Substitution and expression value

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Current topic Strong skill Review due Needs reinforcement To be mastered Optional support

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