Question

If 12x+7y=48 and 17x+12y=68 , then what is the value of x-y? A) 4 C) 6 B)-4 D) -6​

Answer 1

Answer:-

Option (A) 4

Given:-

12x+7y = 48 ...(1)

17x+12y = 68 ...(2)

(1)×12 144x+84y = 576

(2)×7 119x+84y = 476

By elimination,

x(144-119) = 576-476

25x = 100

x = 4. in equ (1),

12(4)+7y = 48

48+7y = 48

7y = 0

y = 0

x-y = 4