y -x =2 and y + x= -2 ,Then ( x+y)(x-y)=?

#19 (no calculator) from test 10

If a-b=119 and a-b=7, what is the value of a?

if x^2 – y^2 = x- y and x<y, what is the average (arithmetic mean) of x and y?

A) 0

B) 1/2

C) 1

D) x/2

E) y/2

How’s everyone else doing on this quiz?