https://vle.mathswatch.co.uk/images/questions/question15829.png

What is the answer to the question on the link please?

Got to give homework back tomorrow

Guest Dec 12, 2018

#1**+2 **

Ok....we have this

924 = 4 ( x + 1) (x + 11) divide both sides by 4

231 = (x + 1) (x + 11) simplify

231 = x^2 + 12x + 11 subtract 231 from both sides

x^2 + 12x - 220 = 0 factor as

(x + 22) ( x - 10) = 0

Set both factors to 0 and solve for x and we get that

x = -22 (reject) or x = 10 (accept)

Dimensions of cuboid are

4, (10 +1), (10 + 11) =

4, 11, 21

CPhill Dec 12, 2018

#2**0 **

Thanks, i checked the answer but still got 5/7 marks. Do you know what elese i need to add?

This is my working:

924 = 4 ( x + 1) (x + 11)

231 = (x + 1) (x + 11)

231 = x^2 + 12x + 11

x^2 + 12x - 220 = 0

(x + 22) ( x - 10) = 0

x=10 x=-22

4, (10 +1), (10 + 11)=

4,11,21

Guest Dec 12, 2018

#3**0 **

https://vle.mathswatch.co.uk/images/questions/question15829.png

What is the answer to the question on the link please?

Got to give homework back tomorrow.

So far, this is my working:

924 = 4 ( x + 1) (x + 11)

231 = (x + 1) (x + 11)

231 = x^2 + 12x + 11

x^2 + 12x - 220 = 0

(x + 22) ( x - 10) = 0

x=10 x=-22

4, (10 +1), (10 + 11)=

4,11,21

… but I still only get 5/7 marks

Do you know what else i need to add?

Guest Dec 12, 2018

#6**0 **

Did you attempt the problem before and get it wrong? if you did, (I know the website you are on ) then even if you get it right the next time, it will only give 5/7, not 7/7. If you attempt two times and get those attempts wrong, but get the third attempt correct, then you score 3/7 points. This process continues al the way until 1/7.

- PM

PartialMathematician Dec 13, 2018