now, there are 12 months in a year, so 18 months is really 18/12 of a year, thus
![~~~~~~ \textit{Simple Interest Earned Amount} \\\\ A=P(1+rt)\qquad \begin{cases} A=\textit{accumulated amount}\dotfill & \$4000\\ P=\textit{original amount deposited}\\ r=rate\to 5\%\to \frac{5}{100}\dotfill &0.05\\ t=years\to \frac{18}{12}\dotfill &\frac{3}{2} \end{cases} \\\\\\ 4000=P[1+(0.05)(\frac{3}{2})]\implies 4000=P(1.075) \\\\\\ \cfrac{4000}{1.075}=P\implies 3720.93\approx P](https://tex.z-dn.net/?f=~~~~~~%20%5Ctextit%7BSimple%20Interest%20Earned%20Amount%7D%20%5C%5C%5C%5C%20A%3DP%281%2Brt%29%5Cqquad%20%5Cbegin%7Bcases%7D%20A%3D%5Ctextit%7Baccumulated%20amount%7D%5Cdotfill%20%26%20%5C%244000%5C%5C%20P%3D%5Ctextit%7Boriginal%20amount%20deposited%7D%5C%5C%20r%3Drate%5Cto%205%5C%25%5Cto%20%5Cfrac%7B5%7D%7B100%7D%5Cdotfill%20%260.05%5C%5C%20t%3Dyears%5Cto%20%5Cfrac%7B18%7D%7B12%7D%5Cdotfill%20%26%5Cfrac%7B3%7D%7B2%7D%20%5Cend%7Bcases%7D%20%5C%5C%5C%5C%5C%5C%204000%3DP%5B1%2B%280.05%29%28%5Cfrac%7B3%7D%7B2%7D%29%5D%5Cimplies%204000%3DP%281.075%29%20%5C%5C%5C%5C%5C%5C%20%5Ccfrac%7B4000%7D%7B1.075%7D%3DP%5Cimplies%203720.93%5Capprox%20P)
Answer:
Solution : ![-\frac{3}{4}-\frac{3}{4}i](https://tex.z-dn.net/?f=-%5Cfrac%7B3%7D%7B4%7D-%5Cfrac%7B3%7D%7B4%7Di)
Step-by-step explanation:
![-3\left[\cos \left(\frac{-\pi }{4}\right)+i\sin \left(\frac{-\pi \:}{4}\right)\right]\:\div \:2\sqrt{2}\left[\cos \left(\frac{-\pi \:\:}{2}\right)+i\sin \left(\frac{-\pi \:\:\:}{2}\right)\right]](https://tex.z-dn.net/?f=-3%5Cleft%5B%5Ccos%20%5Cleft%28%5Cfrac%7B-%5Cpi%20%7D%7B4%7D%5Cright%29%2Bi%5Csin%20%5Cleft%28%5Cfrac%7B-%5Cpi%20%5C%3A%7D%7B4%7D%5Cright%29%5Cright%5D%5C%3A%5Cdiv%20%5C%3A2%5Csqrt%7B2%7D%5Cleft%5B%5Ccos%20%5Cleft%28%5Cfrac%7B-%5Cpi%20%5C%3A%5C%3A%7D%7B2%7D%5Cright%29%2Bi%5Csin%20%5Cleft%28%5Cfrac%7B-%5Cpi%20%5C%3A%5C%3A%5C%3A%7D%7B2%7D%5Cright%29%5Cright%5D)
Let's apply trivial identities here. We know that cos(-π / 4) = √2 / 2, sin(-π / 4) = - √2 / 2, cos(-π / 2) = 0, sin(-π / 2) = - 1. Let's substitute those values,
![\frac{-3\left(\frac{\sqrt{2}}{2}-\frac{\sqrt{2}}{2}i\right)}{2\sqrt{2}\left(0-1\right)i}](https://tex.z-dn.net/?f=%5Cfrac%7B-3%5Cleft%28%5Cfrac%7B%5Csqrt%7B2%7D%7D%7B2%7D-%5Cfrac%7B%5Csqrt%7B2%7D%7D%7B2%7Di%5Cright%29%7D%7B2%5Csqrt%7B2%7D%5Cleft%280-1%5Cright%29i%7D)
=
÷ ![2\sqrt{2}\left(0-1\right)i](https://tex.z-dn.net/?f=2%5Csqrt%7B2%7D%5Cleft%280-1%5Cright%29i)
=
÷ ![-2\sqrt{2}i](https://tex.z-dn.net/?f=-2%5Csqrt%7B2%7Di)
=
÷
=
÷
= ![-\frac{3}{4}-\frac{3}{4}i](https://tex.z-dn.net/?f=-%5Cfrac%7B3%7D%7B4%7D-%5Cfrac%7B3%7D%7B4%7Di)
As you can see your solution is the last option.
Answer:
Average rate of change is <u>0.80.</u>
Step-by-step explanation:
Given:
The two points given are (5, 6) and (15, 14).
Average rate of change is the ratio of the overall change in 'y' and overall change in 'x'. If the overall change in 'y' is positive with 'x', then average rate of change is also positive and vice-versa.
The average rate of change for two points
is given as:
![R=\frac{y_2-y_1}{x_2-x_1}](https://tex.z-dn.net/?f=R%3D%5Cfrac%7By_2-y_1%7D%7Bx_2-x_1%7D)
Plug in
and solve for 'R'. This gives,
![R= \frac{14-6}{15-5}\\\\R=\frac{8}{10}\\\\R=0.80](https://tex.z-dn.net/?f=R%3D%20%5Cfrac%7B14-6%7D%7B15-5%7D%5C%5C%5C%5CR%3D%5Cfrac%7B8%7D%7B10%7D%5C%5C%5C%5CR%3D0.80)
Therefore, the average rate of change for the points (5, 6) and (15, 14) is 0.80.
216+7c=517; 43 copies .... of he made 216 a week from the newspaper and and made 7 dollars per copy sold of his book it should be 216+7c=517 then you subtract 216 from both sides of the equation so 7c=301 then divide 301 by 7 = 43
Answer:
6.907
Step-by-step explanation: