217k views
2 votes
A cuboid with a volume of 924 cm' has dimensions

4 cm, (x + 1) cm and (x + 11) cm.
Show clearly that x2 + 12x – 220 = 0
Solve the equation by factorisation, making sure you show the factorisation.
State both values of x on the same line.
Finally, find the dimensions of the cuboid, writing all three on one line.

2 Answers

4 votes

Answer:

Dimensions = 4cm, 11cm and 21 cm.

Explanation:

x2 + 12x - 220 = 0

x2 + 22x - 10x - 220

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

=(x+22)(x-10)

x + 22= 0

-22 -22

x = -22 (x cant be negative so this is wrong)

x-10 = 0

+10 +10

x = 10 (positive so its correct)

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

= 4, 11, 21 cm.

User Mark Varnas
by
8.2k points
6 votes

Answer:

4cm, 11cm, 21cm

Explanation:

4(x + 1)(x + 11)

4(x ^ 2 + 12x + 44)

x ^ 2 + 12x + 11 = 231

x ^ 2 + 12x + 11 - 231 = 0

x ^ 2 + 12x - 220 = 0

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

x = 10 and x = - 22

4cm , 11cm , 21cm

Hope it helps you xx

User Xdg
by
8.1k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories