To solve this problem you must apply the proccedure shown below:
1. You have that the hyperbola <span>has a vertex at (0,36) and a focus at (0,39).
2. Therefore, the equation of the directrices is:
a=36
a^2=1296
c=39
y=a^2/c
3. When you susbtitute the values of a^2 and c into </span>y=a^2/c, you obtain:
<span>
</span>y=a^2/c
<span> y=1296/13
4. When you simplify:
y=432/13
Therefore, the answer is: </span><span>y = ±432/13</span>
R = 6t.....subbing in (8,48).....t = 8 and r = 48
48 = 6(8)
48 = 48 (correct)
r = 6t...subbing in (13,78)...t = 13 and r = 78
78 = 6(13)
78 = 78 (correct)
so u have 2 sets of points on this line and they are (8,48) and (13,78)
Answer: 
Step-by-step explanation:
Given the following expression:

You need to substitute the given values of "a" and "b" into the expression. Notice that these values are:

Then;

Now you must solve the multiplications:

The final step is to add the numbers. Therefore, you get the following answer:
