A triangular bookshelf has a base of 10 inches, 12 inches, and 18 inches. Will the bookshelf fit in the corner of a square living room?

Not possible

Step-by-step explanation:

Since the triangular base has not a right-angled form. That is, the longest side is greater than value of hypotenuse, meaning that triangular base has a form of a obtuse-angle triangle.

10² + 12² = 18² It is not possible because they dont equal 100 + 144 = 324 244≠ 324