Question

Factorise it.

plzz answer it guyz​

Answer 1

Question-

Factorise-$( {6 \frac{2}{3} })^{2} - ( {2 \frac{1}{3} })^{2}$

Solution -

=$( {6 \frac{2}{3} })^{2} - ( {2 \frac{1}{3} })^{2}$

=$( { \frac{20}{3} })^{2} - ( { \frac{7}{3} })^{2}$

=$( \frac{20}{3} + \frac{7}{3} )( \frac{20}{3} - \frac{7}{3} )$

=$( \frac{20 + 7}{3} )( \frac{20 - 7}{ 3} )$

=$\frac{27}{3} \times \frac{13}{3}$

=$\frac{351}{9}$

=$39$

Formulae

1) a²-b²=(a+b) (a-b)

2) (a+b) ²=a²+b²+2ab

3) (a-b) ²=a²+b²-2ab