As Archer entered he was smiling and looking down on his hostess, who sat on a sofa placed at right angles to the chimney.
Under cover of this circumstantial narrative, to which Mrs. Beaufort listened with her perfect smile, and her head at just the right angle to be seen in profile from the stalls, Madame Olenska turned and spoke in a low voice.
There are no more uses of "right angle" in the book.
Show samples from other sources
The lines intersect at right angles.
He walked slowly toward the truck, his eyes on me the whole way, black beret tilted at exactly the right angle on his head.
Laurie Halse Anderson -- The Impossible Knife of Memory