# [SOLVED] Multiplication of Algerbraic Fractions

• May 12th 2009, 05:03 AM
waven
[SOLVED] Multiplication of Algerbraic Fractions
Q. Simplify:

$\displaystyle \frac {4}{21 - 9x} \div \frac {8}{14 - 6x}$

this is the furthest i've gotten

$\displaystyle \frac {4}{9(3 - x)} \times \frac {2(7 - 3x)}{8}$

the answer is: $\displaystyle \frac 1 3$

im not even sure if my working out so far is right (Worried).

thanks
• May 12th 2009, 05:16 AM
e^(i*pi)
Quote:

Originally Posted by waven
Q. Simplify:

$\displaystyle \frac {4}{21 - 9x} \div \frac {8}{14 - 6x}$

this is the furthest i've gotten

$\displaystyle \frac {4}{9(3 - x)} \times \frac {2(7 - 3x)}{8}$ e^(i*pi) : 9 is not a factor of 21 ;)

the answer is: $\displaystyle \frac 1 3$

im not even sure if my working out so far is right (Worried).

thanks

$\displaystyle \frac {4}{21 - 9x} \div \frac {8}{14 - 6x} = \frac{4}{3(7-3x)} \times \frac{2(7-3x)}{8}$

The 2 and the 4 on the top will cancel with the 8 on the bottom and (7-3x) will cancel to give 1/3