Check the picture below.
now, if AC is that much, recall, BD is the midsegment, thus AB = BC, so AB is just one of the equal halves of AC, so, AB is AC/2.
Use the sum of cubes factoring rule

to transform the left hand side into the right hand side.


Throughout the entire process, the right hand side stayed the same.
On the last step, I used the pythagorean identity.
I think it's the first 7.
I hope this helps :-)
Answer:
<em>The difference is 30 hours</em>
Step-by-step explanation:
<u>Proportions</u>
Safie can write a minimum of 5 questions per hour and a maximum of 11 questions per hour.
To write 275 she takes a maximum of 275/5=55 hours and a minimum of 275/11=25 hours.
The difference is 55 hours - 25 hours = 30 hours