If x² - y² = 55, and x - y = 11, then y =

a. 8

b. 5

c. 3

d. - 8

e. - 3

X^2-y^2=55

this means that

(x+y) (x-y) = 55

we know that x-y=11 so we can write

(x+y) (11) = 55

x+y=55/11 we divide by 11 and we obtain

x+y=5

x-y=11 this means

x=y+11 we replace in the other equation (x+y=5)

y+11+y=5

2y=5-11

2y=-6

y=-3

and you find out that also

x=8