Question

помогите пожалуйста, начиная с 11!! Алгебра 7 класс, пожалуйста!

Answer 1

$11)( frac{10}{3} ) {}^{2} - ( frac{9}{2} ) {}^{2} = frac{100}{9} - frac{81}{4} = \ 11 frac{1}{9} - 20 frac{1}{4} = 11 frac{4}{36} - 20 frac{9}{36} =$
$= - 9 frac{5}{36}$
$12) (frac{31}{6} ) {}^{2} - ( frac{22}{3} ) {}^{2} = frac{961}{36} - frac{484}{9} = \ = 26 frac{25}{36} - 53 frac{7}{9} = 26 frac{25}{36} - 53 frac{28}{36}$
$= - 27 frac{3}{36} = - 27 frac{1}{12}$
$13)(51 - 41)(51 + 41) = \ = 10 times 92 = 920$
$14)(54 - 46)(54 + 46) = \ 8 times 100 = 800$
$15)(76 - 24)(76 + 24) = \ = 52 times 100 = 5200$
$16)(328 - 172)(328 + 172) = \ 156 times 500 = 78000$
$17)( frac{11}{3} ) {}^{2} - ( frac{7}{3} ) {}^{2} = frac{121}{9} - frac{49}{9} \ 13 frac{4}{9} - 5 frac{4}{9} = 8$
$18) (frac{68}{9} ) {}^{2} - ( frac{40}{9} ) {}^{2} = ( frac{68}{9} - frac{40}{9} ) times \( frac{68}{9} + frac{40}{9}) = frac{28}{9} times frac{108}{9} =$
,
$= frac{28 times 12}{9} = frac{28 times 4}{3} = frac{112}{3} = 37 frac{1}{3}$