If x² - y²= 28 and x - y = 8 , then the average of x and y is?
If x² - y²= 28 and x - y = 8 , then the average of x and y is?
Explanation
Given:
x² - y² = 28
x - y = 8
Factor the first equation:
(x - y)(x + y) = 28
Substitute x - y = 8:
8(x + y) = 28
Divide by 8:
x + y = 28/8
x + y = 3.5
The average of x and y is:
(x + y)/2 = 3.5/2 = 1.75