The sum of two numbers is 1. three times the larger number plus two times the smaller number is 18. find the numbers

Let x be the larger number and y be the smaller number; 

x+y=1 <--- x=1-y 

3x+2y=18 

3(1-y)+2y=18 
3-3y+2y=18 
-y=18-3 
-y=15
y=-15 

x+y=1 
x-15=1 
x=1+15 
x=16 

Hope I helped :) 

Did u want to find the value of x?