Maths

Algebra

Adding, Subtracting algebraic formulas

L .O to be able to apply methods of adding and subtracting fractions to algebraic expressions.

When adding or subtracting fractions the first thing you have to ensure is that both sets have

a common denominator just as you would do with a regular numerical calculation. You find the

Lowest Common Multiple of both denominators and adjust the numerators accordingly.

Here both calculations have the same denominator so whether it is an addition or

subtraction calculation only the numerator changes.

There is no common denominator here. The way you tackle this problem is finding the LCM

of 3 and 4 which is 12. So the LCM of 3x and 4x is 12x.

**
**Example 1:

Calculate : X+2/7x + X+ 3/8x =?

Step 1: Look at the numerical parts of the denominator. Here we have 7 and 8 which have a LCM of 56. |

Step 2: Multiply the numerators by 8 and 7 respectively so they both have a common denominator of 56x . |

Step 3: Expand the brackets on the numerators, simplify and re write with the common denominator. |

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