Question

Ifx² - y2 = 80 and x - y = 8 then the average of x and y is
(A) 10
(B) 2
(C)4
(D) 5

Answer 1

Answer:

(D) 5

Step-by-step explanation:

x² - y² = 80 and x - y = 8

Average of x&y=?

--------------

x² - y² = 80

(x+y)(x-y)=80

as x-y=8

8(x+y)=80

x+y=10

Average of x&y is:

(x+y)/2=10/2=5

Correct option is (D) 5