Solving Linear Equation Practice Question

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Question 2

Solve the following linear equation:

Algebra equation r +3 = 9 -2r

Answer

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Select and check your answer...

A. +3
B. -3
C. -2
D. 2

Step by Step Solution

  • Lesson Icon

    Step 1

    To solve the linear equation, add -3 to both sides of the equation to remove +3. The equation becomes:

    r +3 -3 = 9 -2r -3

    Now, on the Left Hand Side (LHS) of the equation, +3 and -3 cancels off. We are left with :

    r = 9 -2r -3
    Algebra equations r = 9 -2r -3
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    Step 2

    Keeping the objective in mind, r = ?, we need to remove -2r on the Right Hand Side (RHS) of the equation. Hence, adding +2r to both sides:

    r +2r = 9 -2r +2r -3

    Now, on the RHS, -2r and +2r cancels off. We are left with:

    r +2r = 9 -3
    Algebra equations r +2r = 9 -3
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    Step 3

    Now, we can simplifying the terms on the LHS by adding r and 2r. This gives 3r.

    3r = 9 -3

    Similarly, simplifying the terms in the RHS adding 9 and -3. This gives 6

    3r = 6
    Algebra equations 3r = 6
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    Step 4

    Realize that to get r = ?, we need to remove 3 from 3r. To do so, we can divide both sides by 3 as shown in the picture.

    Divide '3r = 6' with 3 on both sides

    Now, on the LHS, the we 3 divides by 3 cancels off. So, we are left with r = 6/3.

    r = 6/3
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    Step 5

    Now, on the RHS, 6/3 gives 2. Finally, we have r = 2.

    So, the answer is D.

    Answer is r = 2