Answer:
b=4, 9
Explanation:
b^2-13b+36=0
factor out the trinomial,
(b-4)(b-9)=0
zero property
b-4=0, b-9=0,
b=0+4=4
b=0+9=9
Find two numbers that when they multiply, you get the third term,
which is 36 in this problem. And when they add up, you get the second term,
which is -13 in this problem.