This equation models exponential decay.
We know this because the exponent in the equation is negative, showing us that the growth is “negative”, meaning it represents decay.
Hope this helps!
The question marked angle is equal to 138
2 - 3i is just another of writing (2, -3) in the cartesian plane, the 2-3i however is using the "imaginary axis" for the imaginary plane, is all however the imaginary axis is simply the equivalent of the y-axis. Likewise 9+21i is just (9,21), so let's just use the distance formula.
![\bf ~~~~~~~~~~~~\textit{distance between 2 points} \\\\ (\stackrel{x_1}{2}~,~\stackrel{y_1}{-3})\qquad (\stackrel{x_2}{9}~,~\stackrel{y_2}{21})\qquad \qquad d = \sqrt{( x_2- x_1)^2 + ( y_2- y_1)^2} \\\\\\ d=\sqrt{[9-2]^2+[21-(-3)]^2}\implies d=\sqrt{(9-2)^2+(21+3)^2} \\\\\\ d=\sqrt{7^2+24^2}\implies d=\sqrt{49+576}\implies d=\sqrt{625}\implies d=25](https://tex.z-dn.net/?f=%5Cbf%20~~~~~~~~~~~~%5Ctextit%7Bdistance%20between%202%20points%7D%20%5C%5C%5C%5C%20%28%5Cstackrel%7Bx_1%7D%7B2%7D~%2C~%5Cstackrel%7By_1%7D%7B-3%7D%29%5Cqquad%20%28%5Cstackrel%7Bx_2%7D%7B9%7D~%2C~%5Cstackrel%7By_2%7D%7B21%7D%29%5Cqquad%20%5Cqquad%20d%20%3D%20%5Csqrt%7B%28%20x_2-%20x_1%29%5E2%20%2B%20%28%20y_2-%20y_1%29%5E2%7D%20%5C%5C%5C%5C%5C%5C%20d%3D%5Csqrt%7B%5B9-2%5D%5E2%2B%5B21-%28-3%29%5D%5E2%7D%5Cimplies%20d%3D%5Csqrt%7B%289-2%29%5E2%2B%2821%2B3%29%5E2%7D%20%5C%5C%5C%5C%5C%5C%20d%3D%5Csqrt%7B7%5E2%2B24%5E2%7D%5Cimplies%20d%3D%5Csqrt%7B49%2B576%7D%5Cimplies%20d%3D%5Csqrt%7B625%7D%5Cimplies%20d%3D25)
Answer:
4 hours
Step-by-step explanation:
if you have $350
you'd subtract 50 por que it's a one time fee.
which leaves with 300
then you'd divide 75 into 300
to see how many hours you'd receive with the remaining of your $300.
which is four.