Question

Write an exponential function whose graph passes through the points (0,-2) and (2,-50)

Answer 1

first sub in (0,-2) to get

-2 = ab^0, but b^0 = 1

so a=-2

so far we have

y = -2b^x

now use the other point (2,-50)

-50 = -2(b^2)

b^2 = 25

b= ±5

however in exponentional equations the base is usually positve, so now you have

y = -2(5^x)

sub in x=-2 and you got it.

Explanation:

hope it helps..