A picture is to be mounted on a board show that the picture and board are not mathematically similar

In the polynomial below, what number should replace the question mark to produce a difference of squares? x2 + ? x - 36

The measures of the legs of a right triangle are 15m and 20m . what is the length of the hypotenuse

Non-euclidean geometry was discovered when, in seeking cleaner alternatives to the fifth postulate, it was found that the negation could also be true a. true b.false