Question

Помогите, прошу. Срочно нужно, пожалуйста!!

Answer 1

$\displaystyle\tt 64-b^2=8^2-b^2=(8-b)(8+b)\\\\ 2.89-d^2=1.7^2-d^2=(1.7-d)(1.7+d)\\\\ \frac{100}{121}-y^2=\bigg(\frac{10}{11}\bigg)^2-y^2=\bigg(\frac{10}{11}-y\bigg)\bigg(\frac{10}{11}+y\bigg)\\\\ t^2-\frac{400}{441}=t^2-\bigg(\frac{20}{21}\bigg)^2=\bigg(t-\frac{20}{21}\bigg)\bigg(t+\frac{20}{21}\bigg)\\\\ -16+49y^2=(7y)^2-4^2=(7y-4)(7y+4)\\\\ \frac{4}{25}t^2-36=\bigg(\frac{2}{5}t\bigg)^2-6^2=\bigg(\frac{2}{5}t-6\bigg)\bigg(\frac{2}{5}t+6\bigg)$