$$x^2 - 9 = 0$$
$$x^2 = 9$$
$$x = \pm 3$$
$$0,5^{6-2x} = 32$$
$$(2^{-1})^{6-2x} = 2^5$$
$$2^{2x-6} = 2^5$$
$$2x - 6 = 5$$
$$2x = 11$$
$$x = 5,5$$
$$\log_7(2x+5) = 1$$
$$2x+5 = 7^1$$
$$2x+5 = 7$$
$$2x = 2$$
$$x = 1$$
Ответ: 1) ±3; 2) 5,5; 3) 1