L LEG7930 New member Joined Aug 29, 2010 Messages 17 Aug 29, 2010 #1 Simplify the compound fractional expression (give answer in factored form). [2x^(-2) + 2y^(-2)] / [7x^(-1) + 7y^(-1)] I cannot get this I have tried everything I know!
Simplify the compound fractional expression (give answer in factored form). [2x^(-2) + 2y^(-2)] / [7x^(-1) + 7y^(-1)] I cannot get this I have tried everything I know!
B BigGlenntheHeavy Senior Member Joined Mar 8, 2009 Messages 1,577 Aug 29, 2010 #2 \(\displaystyle \frac{2x^{-2}+2y^{-2}}{7x^{-1}+7y^{-1}} \ = \ \frac{\frac{2}{x^2}+\frac{2}{y^2}}{\frac{7}{x}+\frac{7}{y}} \ = \ \frac{\frac{2x^2+2y^2}{x^2y^2}}{\frac{7x+7y}{xy}}\) \(\displaystyle = \ \frac{2x^2+2y^2}{x^2y^2} \ * \ \frac{xy}{7x+7y} \ = \ \frac{2(x^2+y^2)}{7xy(x+y)}\) \(\displaystyle Did \ you \ read \ more \ into \ it \ than \ there \ was?\)
\(\displaystyle \frac{2x^{-2}+2y^{-2}}{7x^{-1}+7y^{-1}} \ = \ \frac{\frac{2}{x^2}+\frac{2}{y^2}}{\frac{7}{x}+\frac{7}{y}} \ = \ \frac{\frac{2x^2+2y^2}{x^2y^2}}{\frac{7x+7y}{xy}}\) \(\displaystyle = \ \frac{2x^2+2y^2}{x^2y^2} \ * \ \frac{xy}{7x+7y} \ = \ \frac{2(x^2+y^2)}{7xy(x+y)}\) \(\displaystyle Did \ you \ read \ more \ into \ it \ than \ there \ was?\)
L LEG7930 New member Joined Aug 29, 2010 Messages 17 Aug 29, 2010 #3 thanks so much! I think the 2 and the 7 were what were throwing me off for some reason.
