Give an example of an open equation? my answer is, x + 4 = 7 until the value of x is found, it is unknown whether the equation is true or false. am i right?

What is the length of the segment joining the points at (4,5) and (6,-2) round to the nearest tenth if necessary

Aman is 6 feet 3 inches tall. the top of his shadow touches a fire hydrant that is 13 feet 6 inches away. what is the angle of elevation from the base of the fire hydrant to the top of the man's head?

What is the ratio of the length of an object in yards to the length of the same object in miles?