Which of the following is the graph in the xy-plane of the given equation?
Choice D is correct. The y-intercept of the graph of an equation is the point , where b is the value of y when
. For the given equation,
when
. It follows that the y-intercept of the graph of the given equation is
. Additionally, for the given equation, the value of y doubles for each increase of 1 in the value of x. Therefore, the graph contains the points
,
,
, and
. Only the graph shown in choice D passes through these points.
Choices A and B are incorrect because these are graphs of decreasing, not increasing, exponential functions. Choice C is incorrect because the value of y increases by a growth factor greater than 2 for each increase of 1 in the value of x.