[Math] Area of the shaded part in rectangle

geometryrectangles

area problem
The question asks you to determine the shaded part of the rectangle in terms of x.

please will someone help with this problem, i have spent a while on it with not much progress.

Best Answer

Given the information in the picture, $x$ does not uniquely define the area of the gray area, therefore it is impossible to express the area only in terms of $x$.