Answer:

Step-by-step explanation:
The graph you see there is called a parabola. The general equation for the graph is as below

To find the equation we need to find the constants a and b. The constant b is just how much we're lifting the parabola by. Notice it's lifted by 1 on the y axis.
To find a it's a little more tricky. Let's use the graph to find a value for a by plugging in values we know. We know that b is 1 from the previous step, and we know that when x=1, y=3. Let's use that!

Awesome, we've found both values. And we can write the result.

I'll include a plotted graph with our equation just so you can verify it is indeed the same.
Assume the parabola is placed on a graph where the x-axis is the top of the dish.
The vertex is then at (0,-30) The x-intercepts or zeros are at (-30,0) and (30,0)
The equation of such parabola would be:

Plug in vertex to find value of 'a'

Now find the focus given that


Answer: the microphone should be placed 7.5 inches from vertex.
I don’t know if that 2 and 1/4 or 21/4 so I’ll do both.
2 and 1/4 is = 9/4
21/4 is = 5 and 1/4
Answer:
ill answer the answers asap in the comments section
Answer:
lesser x = -4
greater x = 1
Step-by-step explanation:
here's the solution :-
=》

=》

=》

=》

now, there are two cases
case 1) where x + 4 = 0
=》x = -4
case 2) where x - 1 = 0
=》x = 1