Two Numbers with a Sum of 28 and a Difference of 3

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 =  15.5
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 =  12.5
Therefore, the two Numbers are 15.5 and 12.5
Check Sum of the two Numbers:

		1
	1	5	.	5
	1	2	.	5
	2	8	.	0

15.5 + 12.5 = 28 (trailing zero and decimal point are dropped) ✓
Check Difference between the two Numbers:

	1	5	.	5
−	1	2	.	5
		3	.	0

15.5 − 12.5 = 3 (trailing zero and decimal point are dropped) ✓