Question

Помогите решить, пожалуйста

Answer 1

Ответ:

2,5

Объяснение:

$( \sqrt{8 + a} + \sqrt{3 - a} )^{2} = {4}^{2} \\ 8 + a + 2 \sqrt{(8 + a)(3 - a)} + 3 - a = 16 \\ 8 + 3 + 2 \sqrt{(8 + a)(3 - a)} = 16 \\ 2 \sqrt{(8 + a)(3 - a)} = 16 - 11 \\ 2 \sqrt{(8 + a)(3 - a)} = 5 \\ \sqrt{(8 + a)(3 - a)} = 5 \div 2 = 2.5$

Answer 2

$\sqrt{8+a} +\sqrt{3-a}=4 \\\\(\sqrt{8+a} +\sqrt{3-a})^{2} =4^{2}\\\\(\sqrt{8+a})^{2}+2*\sqrt{(8+a)(3-a)}+(\sqrt{3-a} )^{2}=16\\\\8+2+2\sqrt{(8+a)(3-a)}+3-a=16\\\\11+2\sqrt{(8+a)(3-a)}=16\\\\2\sqrt{(8+a)(3-a)}=5\\\\\boxed{\sqrt{(8+a)(3-a)}=2,5}$