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PLEASE HHELP!!! Bring the fraction:

b/7a^2c to a denominator of 35a^3c^3



a/a-4 to a denominator of 16-a^2

User Proactif
by
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1 Answer

4 votes

Answer:


(b)/(7a^2c) = (5abc^2)/(35a^3c^3)


(a)/(a - 4) = (-a^2 - 4a)/(16 -a^2)

Explanation:

Given


(b)/(7a^2c)

Express the denominator as
35a^3c^3

To do this, we divide
35a^3c^3 by the denominator


(35a^3c^3)/(7a^2c) = 5ac^2

So, the required fraction is:


(b)/(7a^2c) * (5ac^2)/(5ac^2)


(5abc^2)/(35a^3c^3)

Hence:


(b)/(7a^2c) = (5abc^2)/(35a^3c^3)

Given


(a)/(a - 4)

Express the denominator as
16 - a^2

Multiply the fraction a+4/a+4

So, we have:


(a)/(a - 4) * ((a + 4))/((a + 4))

Apply difference of two squares to the denominator


(a^2 + 4a)/(a^2 - 16)

Take the additive inverse of the numerator and denominator


(-(a^2 + 4a))/(-(a^2 - 16))


(-a^2 - 4a)/(16 -a^2)

Hence:


(a)/(a - 4) = (-a^2 - 4a)/(16 -a^2)

User Jedo
by
3.5k points