Question 481576
Try this:
Let the two numbers be a and b, then:
a+b = 52 and
a = 3b Substitute this for a in the first equation.
3b+b = 52 Simplify.
4b = 52 Divide both sides by 4.
b = 13 and
a = 3(13)
a = 39
Check:
13+39 = 52.