The total surface area of the walls of a room 7m long, 5m wide and xm high is 96m2. Find the value of x

A.
(frac{2}{3}) 
B.
2 
C.
4 
D.
8
Correct Answer: Option B
Explanation
T.S.A of the wall (=2(7times 5 + 7 times x + 5 times x) = 96\
70 + 14x + 10x = 96 Rightarrow 24x = 9670=26\
x = frac{26}{24}=frac{13}{12})