AS we know that:

And we have the volume and we can calculate the SA,,,
So that, we can conclude:

Are you
satisfied?
200 is the answer because 500-300 is 200
To find the length of a square given the area, we just need to take the square root of the area given. The sqrt of 36 is 6, so each side is 6 inches. :)
2x^2 + 8x - 12 = 0..divide by 2
x^2 + 4x - 6 = 0
x^2 + 4x = 6...add 4 to both sides of the equation
x^2 + 4x + 4 = 6 + 4
(x + 2)^2 = 10....<== ur constant is 10
x + 2 = (+-)sqrt 10
x = -2 (+ - ) sqrt 10
x = -2 + sqrt 10
x = -2 - sqrt 10