x+y = 17 এবং xy = 60 হলে x-y = কত?

x+y = 17 এবং xy = 60 হলে x-y = কত?

A 7

B 8

C 9

D 10

Solution

Correct Answer: Option A

(x-y)²=(x+y)²-4xy
=(17)²-4.60
বা,(x-y)²=49
বা,x-y=7