The question is asking us to find two numbers which when added will give us 15 and when multiplied will give us 36.
We can find the numbers from the factors of 36 .
Let us look at the numbers that multiply to give us 36.
36=2x13
36=3x12..........................3+12=15
36=4x9
36=6x6
36=36x1
Out of these pair of numbers we will look for the pair which when added will give 15
12+3=15.
We got the two numbers which when multiplied will give 36 and when added 15.
The numbers 3 and 12 when multiplied will give 36 and the sum of these numbers is 15.