This may be your first algebra lesson. In case you are rather uncomfortable with algebra, you may want to first go through Basic Algebra - An Introduction - that would give you a good foundation before this lesson.
This Algebra Lesson introduces a technique known as 'transposition'. This is the most common way to solve algebra equations. A quick review here of the basic principles - all equations have two sides: a Left Side (LS) and a Right Side (RS). In the example below 3x + 4 is on the Left Side of the equation and 31 is on the Right Side of the equation:
3x + 4 = 31
LS RS
The common transposition method is to do the same thing (mathematically) to both sides of the equation, with the aim of bringing like terms together and isolating the variable (or the unknown quantity).
So, to solve this equation, first subtract 4 from both sides of the equation. This will get rid of number 4 from the LS
3x + 4 - 4 = 31 - 4That will give us:
3x = 27Now, looking at the LS we have 3x. So we need to divide it by 3 to isolate x, and we need to do the same to the RS.
\(\frac{{3x}}{3} = \frac{{27}}{3}\)Now that gives us:
\(x = \frac{{27}}{3} = 9\)Check Our Answer:
3x + 4 = 31
3 × 9 + 4 = 31
27 + 4 = 31
31 = 31
So, our answer x = 9 is correct.
That's the algebra lesson on transposition. Now, you are ready to review some examples to further develop your understanding of transposition.
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