math
posted by Ellen .
The difference of two numbers is 9. The sum of 3 times the greater number and 4 more than the lesser number is 51. What are the two numbers?
I do not get this question... I have tried many times, but can not get it.. please help!
thank you.

LS=9
3L+S+4=51
can you take it from here? 
the sum of two numbers is 20. the greater number is 4 more than the lesser. what are the two numbers? write the equation.