Question 1084859
To find what age John is, we use x to indicate it. Then Sarah's age will be x÷2 and his father Mr Hughes's age will be 5*x. Their combined age after two years will be following:
  5*x+2+x+2+x÷2+2=58 
  6*x+x÷2=52.  And now we multiply 2 to each side 
  12*x+x= 104
  13*x=104
  x=8. So as it is seen, John is 8 years old.