Without working a quadratic equation, we can examine the divisors of 36 for a pair that add to 15.
1*36 = 36 1+36 = 37
2*18 = 36 2+18 = 20
3*12 = 36 3+12 = 15
Your two numbers are 3, 12
1*36 = 36 1+36 = 37
2*18 = 36 2+18 = 20
3*12 = 36 3+12 = 15
Your two numbers are 3, 12