Question

factorise the following 25/(l)2-49/(m)2​

Answer 1

Solution :

$\frac{25}{l^{2}}-\frac{49}{m^{2}}$

= $\frac{5^{2}}{l^{2}}-\frac{7^{2}}{m^{2}}$

=$\left (\frac{5}{l}\right )^{2}-\left(\frac{7}{m}\right)^{2}$

= $\left(\frac{5}{l}+\frac{7}{m}\right)\left((\frac{5}{l}-\frac{7}{m}\right)$

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