. If 9x-3y=12 and 3x-5y=7 then 6x-2y = ?

A.-5
B. 4
C. 2
D. 8

Ans. D

• 9x-3y=12 and 3x-5y=7 or 9x-15y = 21
  
  so 12 y =-9
  y=-9/12= -3/4
  9x= 3y+12= 12-9/4 = 39/4
  x= 39/36=13/12
  
  6x-2y = 6*13/12 - 2*(-3/4) =13/2 +3/2 =16/2 =8..option D
• 11 years agoHelpfull: Yes(9) No(3)
• 9x-3y=12....(1) & 3x-5y=7....(2)
  multiplying 2nd equation by 3 & equaling two equation
  y=-3/4 & x=13/12
  then 6x-2y=6(13/12) - 2(-3/4)
  =(13/2)+(3/2)
  =16/2=8(option D)
  
• 11 years agoHelpfull: Yes(2) No(0)
• in an hotel,we can order 2 types of varieties.,but we can make 6 more varieties at home.One can choose 4 varieties with 2 from hotel as must.find how many ways one can order???
  please provide solution to this?
• 11 years agoHelpfull: Yes(0) No(3)
• garima....from where 12 y= -9 came?
• 11 years agoHelpfull: Yes(0) No(2)