Question 1112920
 Find the value of two numbers if their sum is 70
a + b = 70
 and their difference is 36.
a - b = 36
:
Use elimination on these two equations
a + b = 70
a - b = 16
------------Addition eliminates b, find a
2a + 0 = 86
a = 86/2
a = 43
Find b
43 + b = 70
b = 70 - 43
b = 27
:
:
Check 
43 - 27 = 16