The sum of two numbers is 110. Their difference is 28. What is the smallest of the two numbers?

Question

phi · Answer

This is algebra.  Give the two unknown numbers names.  For example, x and y
now use x and y in two different equations:
the sum of x and y is 110.  Can you make that into an equation?
the difference of x and y is 28.  Can you make that into an equation?

experimentx · Answer

x+y = 110
x-y = 28

x = 69
y = 41

seems only one possible solution

anonymous · Answer

x+y= 110 and x-y=28

anonymous · Answer

Thank you so much(:!

phi · Answer

Yes.  Good job.  
One easy way to solve is add the two equations together
x+y + (x-y) = 110+28
the y's cancel, and the x's add up to 2x, so you get
2x= 138
x= 69
because x+y= 110  we know 69+y= 110
subtract 69 from both sides to get y= 41

anonymous · Answer

Thank you!! This makes so much more sense to me now!