ANSWER

EXPLANATION
Use the Pythagoras Theorem to obtain,

This implies that,


Take the positive square root of both sides to get,


Now what you want to do is 21 + (-3). Since this is the same as saying 21 - 3, the answer is 18. Therefore, the answer is 18°F.
Answer:

Step-by-step explanation:
35 marks out of 40<u> as a fraction:</u>
35 / 40
<u>As a percentage:</u>
<u></u>![\sf \frac{35}{40} * 100 \ \%\\\\0.875 * 100 \ \%\\\\87.5 \ \%\\\\\rule[225]{225}{2}](https://tex.z-dn.net/?f=%5Csf%20%5Cfrac%7B35%7D%7B40%7D%20%2A%20100%20%5C%20%5C%25%5C%5C%5C%5C0.875%20%2A%20100%20%5C%20%5C%25%5C%5C%5C%5C87.5%20%5C%20%5C%25%5C%5C%5C%5C%5Crule%5B225%5D%7B225%7D%7B2%7D)
Hope this helped!
<h3>~AH1807</h3>
Answer:

Step-by-step explanation:
Given




Required
Find the height
The volume is calculated as thus:

This gives

Apply difference of two squares


Subtract 15 from both sides

Using a calculator to factorize, we have:

Split
or 
or 
x has complex roots for 
Hence:

Recall that:

