Question

Помогите с алгеброй 31.5

Answer 1

$1) 13^2-9^2=(13-9)(13+9)=4*22 =88 \ \ 2) 2.2^2-2.8^2=(2.2-2.8)(2.2+2.8)=-0.6*5=-3 \ \ 3) ( frac{5}{6} )^2-( frac{2}{3} )^2=( frac{5}{6}- frac{2}{3} )( frac{5}{6}+frac{2}{3} )= frac{5-4}{6}* frac{5+4}{6} = frac{1}{6}* frac{9}{6} = frac{1}{4}$