Answer:
23
Step-by-step explanation:
-The length of the cubes side is (x-5) and the total surface area is 1944 sq units.
-We apply the formula for surface area and equate to solve for x:
[tex]A=6s^2\\\\1944=6(x-5)^2\\\\324=(x-5)^2\\\\324=x^2-10x+25[/tex]
#Equate to zero as below:
[tex]324=x^2-10x+25\\\\x^2-10x+25-324=0\\\\x^2-10x-299=0\\\\\# Quadratic \ Formula:\\\\x_{1,2}=\frac{-b\pm \sqrt{b^2-4ac}}{2a}\\\\\\=\frac{10\pm\sqrt{(-10)^2-4(1\times-299)}}{2\times1}\\\\x_1=23, \ \ \ x_2=-13[/tex]
length dimensions are always positive.
Hence, the value of x is 23