Answer:
The larger number is 51 and the smaller number is 12
Explanation:
Let
x -----> the larger number
y ----> the smaller number
we know that
the larger of two numbers is 15 more than three times the smaller number
 -----> equation A
 -----> equation A
the sum of the two numbers is 63
 ----> equation B
 ----> equation B
substitute equation A in equation B and solve for y
 
 
 
 
 
 
 
 
 
 
Find the value of x
 ---->
 ----> 

therefore
The larger number is 51 and the smaller number is 12