Write the equation of an exponential function that has a horizontal asymptote at y=3, and a y-intercept at (0,4) and passes through the point (-1,6).

Please explain how to go through this, i dont want only answers

Question

Write the equation of an exponential function that has a horizontal asymptote at y=3, and a y-intercept at (0,4) and passes through the point (-1,6).

Please explain how to go through this, i dont want only answers

sirm3d · Answer

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$$\large y=a\cdot b^{-x}+c$$
the line $y=c$ is the asymptote

anonymous · Answer

i confused on how i would get a or b, i have this so far:
+3
lol and nothing else

sirm3d · Answer

when x=0, y=4
$$4=a\cdot b^0+3$$ but b^0=1

sirm3d · Answer

so a=1

finally, when x=-1, y=6
solve b in $$6=b^{-1}+3$$

sirm3d · Answer

uhm, i mean

$$6=b^{-(-1)}+3$$
or $$6=b+3$$

anonymous · Answer

okay so b is 3
y=3^-x +3?