Question

 If x+y=6, x-y=4 find xy=? *

options:-

(i)4

(ii)6

(iii)5

(iv)7

​

Answer 1

Answer:

x+y=6...... equation 1

x=6-y

x-y=4....... equation 2

put value of x =6-y in equation 2

6-y-y=4

6-2y=4

-2y=4-6

y=1

and xy =5

Answer 2

♥ x + y = 6 equ.(1)

x = 6 - y

♥ x - y = 4 equ.(2)

substituting x = 6 - y

6 - y - y = 4

- 2y = 4 - 6

- 2y = - 2

y = -2/-2

y = 1

Substituting y = 1 in equ.(1)

x + 1 = 6

x = 6 - 1

x = 5

♥ xy = 5 x 1

Answer ➡️ 5