Solving Multi-Step Equations

Solving Multi-Step Equations

Grade 9th Grade · Math · 45 min

What's Included

Learning Objective

I can solve multi-step linear equations by using inverse operations to isolate the variable.

Reading Passage

Solving Multi-Step Equations

Solving multi-step linear equations is a fundamental skill in algebra, requiring a systematic approach to find the value of an unknown variable. The primary objective is always to "isolate" the variable, meaning to get it by itself on one side of the equals sign. To achieve this, we use inverse operations, which are mathematical actions that undo each other. For instance, addition is the inverse of subtraction, and multiplication is the inverse of division.

When solving multi-step equations, it is crucial to undo operations in the reverse order of how they would typically be performed. This generally means addressing addition and subtraction first, followed by multiplication and division. If there are like terms on one side of the equation, such as 3x + 2x, you should combine them to simplify before applying inverse operations.

Consider the equation 2x + 5 = 15. To isolate 'x', first undo the addition of 5 by subtracting 5 from both sides, which gives 2x = 10. Next, undo the multiplication by 2 by dividing both sides by 2, resulting in x = 5. It is essential to remember that any operation performed on one side of the equation must also be performed on the other side to maintain balance. Mastering this process allows you to confidently solve a wide range of algebraic problems.

Warm-Up Video

Mathispower4u · 5:52

Ex2A : Solve Multi-Step Linear Equations in One Variable

Guided Notes

3 key concepts

  • 1

    To simplify each side of a multi-step equation, you must first clear the parentheses and then combine like terms.

  • 2

    To isolate the variable term, you should use addition or subtraction to move all variable terms to one side and all constant terms to the other.

  • 3

    The final step to isolate the variable is to use multiplication or division to undo the operation between the coefficient and the variable.

Practice Questions

10 questions · Multiple choice & Short answer

Exit Ticket

Quick comprehension check

Solve the following multi-step linear equation for x, showing all steps: 5(3x - 2) = -3(x + 4)

Complete Lesson Package

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