The reflecting dish of a parabolic microphone has a cross-section in the shape of a parabola. the microphone itself is placed on the focus of the parabola. if the parabola is 24 inches wide and 4 inches deep, how far from the vertex should the microphone be placed? (1 point)
4 inches
18 inches
9 inches
12 inches

step-by-step explanation:

f(x)=2x^2 -1 

translation is a function transformation that transform the function in a way of translating. by translating the function its graph is moved  up an down. moving the function f(x) 2 units to the left will be the new function g(x) with the equation: g(x)=f(x+2)=2(x+2)^2 -1

it would open into a square depending on the type of envelope i’m not sure about the second part