Answer:
The student incorrectly simplified 10ab root 2a + 20a root 2a
Step-by-step explanation:
Answer:
4
Step-by-step explanation:
Answer: 
Step-by-step explanation:



Answer:
not sure about this one sryyy
Step-by-step explanation:
i ll try to figure it out
a)
well, she put 4000, and she earned in interest 960, so her accumulated amount is just their sum, 4960.
b)
now, it doesn't say, so we're assuming is <u>simple interest</u>, as opposed to compound interest.

c)
let's make the rate 1% greater then, and check
![\bf ~~~~~~ \textit{Simple Interest Earned} \\\\ I = Prt\qquad \begin{cases} I=\textit{interest earned}\dotfill\\ P=\textit{original amount deposited}\dotfill & \$4000\\ r=rate\to \stackrel{8+1}{9\%}\to \frac{9}{100}\dotfill&0.09\\ t=years\dotfill &3 \end{cases} \\\\\\ I=(4000)(0.09)(3)\implies I=1080 \\\\[-0.35em] ~\dotfill\\\\ \stackrel{\textit{at 9\%}}{1080}-\stackrel{\textit{at 8\%}}{960}\implies \stackrel{\textit{that much more}}{120}](https://tex.z-dn.net/?f=%5Cbf%20~~~~~~%20%5Ctextit%7BSimple%20Interest%20Earned%7D%20%5C%5C%5C%5C%20I%20%3D%20Prt%5Cqquad%20%5Cbegin%7Bcases%7D%20I%3D%5Ctextit%7Binterest%20earned%7D%5Cdotfill%5C%5C%20P%3D%5Ctextit%7Boriginal%20amount%20deposited%7D%5Cdotfill%20%26%20%5C%244000%5C%5C%20r%3Drate%5Cto%20%5Cstackrel%7B8%2B1%7D%7B9%5C%25%7D%5Cto%20%5Cfrac%7B9%7D%7B100%7D%5Cdotfill%260.09%5C%5C%20t%3Dyears%5Cdotfill%20%263%20%5Cend%7Bcases%7D%20%5C%5C%5C%5C%5C%5C%20I%3D%284000%29%280.09%29%283%29%5Cimplies%20I%3D1080%20%5C%5C%5C%5C%5B-0.35em%5D%20~%5Cdotfill%5C%5C%5C%5C%20%5Cstackrel%7B%5Ctextit%7Bat%209%5C%25%7D%7D%7B1080%7D-%5Cstackrel%7B%5Ctextit%7Bat%208%5C%25%7D%7D%7B960%7D%5Cimplies%20%5Cstackrel%7B%5Ctextit%7Bthat%20much%20more%7D%7D%7B120%7D)