Question

The sum of two numbers is fifteen. The product of the two numbers is thirty six. Find the numbers

Answer 1

One way is to find the factors of 36
factors are
1,36
2,18
3,12
4,9
6,6
add them
1+36=37
2+18=20
3+12=15 match
4+9=13
6+6=12

the numbesr are 3 and 12

Answer 2

Best to take this in two parts. 

1, find the factors of 36:
1 and 36
2 and 18
3 and 12
4 and 9
6 and 6

2, Now, using those, add the factors and see which add up to 15... in this case, that would be 12 and 3!