Question

Find all x,y (belongs to)N when xy - 4 = 2x + y​

Answer 1

Answer:

Solution set (x, y) = { (7, 3), (4, 4), (3, 5), (2, 8) }

Step-by-step explanation:

Given :

xy - 4 = 2x + y

To find :

all x, y ∈ N

Solution :

xy - 4 = 2x + y

=> xy - 2x = y + 4

=> x (y - 2) = y + 4

=> x = (y + 4)/(y - 2)

=> x = 1 + [ 6 /(y - 2) ]

Now, y can not be equal to or less than 2 and can not be more than 8. {since, x, y ∈ N }

for, y = 3, x = 7.

for y = 4, x = 4.

for y = 5, x = 3

for y = 8, x = 2

Hence, all possible solutions are ;

(x, y) = { (7, 3), (4, 4), (3, 5), (2, 8) }