Exponential Equation
We are given the following values of x and y:
x={-2,-1,0,1,2,3}
y={12,6,3,3/2,3/4,3/8}
It's required to find the equation that models the table.
The model to use is exponential, which general formula is:
Where A and r are values to determine with the data provided in the table.
Let's use the first two values: x=-2, y=12:
Now use the second pair: x=-1, y=6
Dividing the second equation by the first:
Thus, r = 1/2 = 0.5Thus
Substituting the value of r in any of the two equations (for example the first one):
Operating:
Solving for A:Solving for A
A = 12/4 = 3
Thus, the required equation is:
Note we only used two points to determine the equation. The rest of the points from the table should satisfty the equation. We'll only check one of them, for example x=0, y=3
The point satisfies the equation and the rest of the points will also dosfies the equation and
Answer: B