Which relation defined by a mapping diagram is a function?

answer

d. 10

explanation

the distance from point y to wx is the height of the triangle.

using pythagoras theorem,

group similar terms to get,

this implies that,

take positive square root of both sides to get,

this implies that,

-22

times both sides by 2, times () by 8, add alile terms, move terms, add alike and caculate divide both sides by 3