What is the simplified algebraic expression for the total area of the figure?

To find the area of a square or a rectangle , you just need to multiply the length by the width
To find the area of a triangle , you just need to multiply the base by the the side and divide that by 2

Square : As squares have congurent sides , both its length and width are x. Length × Width = x times x which is x^2

Rectangle: 2x times x which is 2x^2

Triangle : ( x × 2x ) ÷ 2
2x^2 ÷ 2 which is x^2

Now we just need to add all of them :
x^2 + 2x^2 + x^2 = 4x^2

Awnser : The area of the figure is 4x^2