Answer:
3 teaspoons
Step-by-step explanation:
Let's take a look at a perfect square trinomial.

We can distribute this expression to get

.
An important relation to recognize here is that the constant is the square of half of the x value.
Now, if we wanted to add a number to

to make a perfect square trinomial, we could have the value of x and then square it.
Half of 16 is 8, and 8 squared is
I don't know hibgiuuibbohubhouhigohiboihbobihioijboib
4/6
10/15
6/9
8/12
Hope these help you!!! =')