She sat on a low stool at nearly a right angle with the two boys, watching first one and then the other; and Philip, looking off his book once toward the fire-place, caught the pair of questioning dark eyes fixed upon him.
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