Explanation

We are asked to find the value of $b$.

Step 1: Start with the given

$$abc = a^2 quad text{and} quad ac = 2$$

Step 2: Substitute
$ac=2$ into the first equation

abc=a^2 ⇒b(ac)=a^2⇒b(2)=a^2

Step 3: Solve for b

$$$$
2b=a^2⇒b=a^2/2​