Question

Помогите решить задание.

Answer 1

Объяснение:

$\sqrt{2 \frac{7}{9} } - 5 \sqrt{1.96} = \\ = \sqrt{ \frac{25}{9} } - 5 \times 1.4 = \\ = \frac{5}{3} - 7 = 1 \frac{2}{3} - 7 = - 6 \frac{2}{3}$

$\sqrt{2.5} \times \sqrt{14 \frac{2}{5} } = \\ = \sqrt{2.5 \times 14.4} = \\ = \sqrt{0.25 \times 144} = 0.5 \times 12 = 6$

$\sqrt{80} \div 5 = \sqrt{80 \div 5} = \sqrt{16} = 4$

${( - 2 \sqrt{7} )}^{2} = {( - 2)}^{2} \times ( \sqrt{7}) {}^{2} = \\ = 4 \times 7 = 28$