How many cats do you have if you had 9 and sell 2 and buy 6 more then sell5 then get 19 then sell 4 then buy 54 then sell 39 and buy an elephant?

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,