Two Numbers with a Sum of 90 and a Difference of 36

Define variables:
Let x = larger number and y = smaller number
Resulting system of equations:
x + y = Sum
x − y = Difference
Solve the system of equations for x (larger number):
x =  

Sum + Difference/2

Find x by substituting given Sum and Difference into equation for x and simplify:
x =  
x =  
x =  63
Solve the system of equations for y (smaller number):
y =  

Sum − Difference/2

Find y by substituting given Sum and Difference into equation for y and simplify:
y =  
y =  
y =  27
Therefore, the two Numbers are 63 and 27
Check Sum of the two Numbers:

	1
	6	3
	2	7
	9	0

63 + 27 = 90 ✓
Check Difference between the two Numbers:

	5	13
	6	3
−	2	7
	3	6

63 − 27 = 36 ✓