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Simplify the complex fraction, rewriting it by multiplying the numerator and denominator by the LCD

Simplify the complex fraction, rewriting it by multiplying the numerator and denominator-example-1
User Lielle
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Given the complex fraction:


((1)/(3)+(4)/(x+5))/((6)/(x+5)+(1)/(5))

You can simplify it as follows:

1. Find the LCD (Least Common Denominator). In this case:


LCD=(3)(5)(x+5)=15(x+5)

2. Multiply the numerator and the denominator of the complex fraction by the LCD, in order to get rid of the denominators of the fractions that form the complex fraction:


=(((1)/(3))\lbrack15(x+5)\rbrack+((4)/(x+5))\lbrack15(x+5)\rbrack)/(((6)/(x+5))\lbrack15(x+5)\rbrack+((1)/(5))\lbrack15(x+5)\rbrack)

Notice that you can simplify multiply and simplify as follows (you can see below the process for simplifying each fraction that forms the complex fraction):


((1)/(3))\lbrack15(x+5)\rbrack=(\lbrack15(x+5)\rbrack)/(3)=5(x+5)
((4)/(x+5))\lbrack15(x+5)\rbrack=(4\lbrack15(x+5)\rbrack)/(x+5)=(60(x+5))/(x+5)=60
((6)/(x+5))\lbrack15(x+5)\rbrack=(6\lbrack15(x+5)\rbrack)/(x+5)=(90(x+5))/(x+5)=90
((1)/(5))\lbrack15(x+5)\rbrack=(\lbrack15(x+5)\rbrack)/(5)=3(x+5)

Then, you can rewrite the expression as follows:


=(5(x+5)+60)/(90+3(x+5))

3. Apply the Distributive Property in the numerator and in the denominator:


=((5)(x)+(5)(5)+(60))/(90+(3)(x)+(3)(5))
=(5x+25+60)/(90+3x+15)

4. Add the like terms in the numerator and in the denominator:


=(5x+85)/(3x+105)

Hence, the answer is:


=(5x+85)/(3x+105)

User Maybe Julius
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