Question

The graph of y = -3x + 2 intersects the graph of an exponential function at (-1, 5). Which of the following could be the exponential function?
a) y = 10(2)$^{x}$
b) y = 10(0.5)$^{x}$
c) y = 5$^{x}$
d) y = 5(2)$^{x}$

Answer 1

Of the function choices offered, only the first includes (-1, 5) in its graph.
  a) y = 10(2)^x

Answer 2

Answer:

$a) y = 10(2)^x$

Step-by-step explanation:

In order to solve this you just need to evaluate the options given with the values of the point that is given in order to see if that point is a possibility in that function, remember to use the value of x to avaluate and if the result is the same as the points value for y then that poin is part of the graph.

$a) y = 10(2)^x$

$y=10(2)^x\\y=10(2)^-1\\y=10*\frac{1}{2} \\y=5$

Remember that when elevating to negative numbers the ecponent becomes a numerator, so the only option that is correct would be the first one $a) y = 10(2)^x$