Ksp x 2x2 72 x 1015 4x3 x 122 x 105 Could you tell me how i

Ksp= x (2x)^2
7.2 x 10^-15 = 4x^3
x= 1.22 x 10^-5

Could you tell me how it got the x= 1.22 x 10^-5?

Solution

7.2 * 10^-15 = 4x^3

Divide 7.2 by 4 we get 1.8

So,

1.8 * 10^-15 = x^3

Taking cube root of the lest side we get:

Cube root of 1.8 is = 1.22

Cube root of 10^-15 is = 10^-5

So, x = 1.22 x 10^-5