Two Numbers with a Sum of 1 and a Difference of 0.7

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 =  0.85
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 =  0.15
Therefore, the two Numbers are 0.85 and 0.15
Check Sum of the two Numbers:

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

0.85 + 0.15 = 1 (trailing zeros and decimal point are dropped) ✓
Check Difference between the two Numbers:

	0	.	8	5
−	0	.	1	5
	0	.	7	0

0.85 − 0.15 = 0.7 (trailing zero is dropped) ✓