6th grade pls help with the question that is circled in black

Explain why the function is discontinuous at the given number a. (select all that apply.) f(x) = 1 x + 1 a = −1 f(−1) is undefined. lim x→−1+ f(x) and lim x→−1− f(x) exist, but are not equal. lim x→−1 f(x) does not exist. f(−1) and lim x→−1 f(x) exist, but are not equal. none of the above

Show your workcan a right triangle have this sides? *how to prove it without using the pythagorean theorema*

Determine if the equation defines y as a function of x: 2xy = 1. yes o no