The required equation of the function that represents the area of the porch is A(x) = 8x² + 38x + 45. Option D is correct.
Given that,
Dan is tiling his rectangular, concrete porch with square, porcelain tiles. The length of the porch is represented by the function l(x)=4x+9, where x is the side length, in feet, of each tile. The width of the porch is represented by the function w(x)=2x+5.
What is surface area?
The surface area of any shape is the area of the shape that is faced or the surface area is the amount of area covering the exterior of a 3D shape.
Here,
Length of the porch = 4x + 9
Width of the porch = 2x + 5
area of the porch A(x) = (4x + 9) (2x + 5 )
= 8x² + 20x + 18x + 45
= 8x ² + 38x + 45
Thus, the required equation of the function that represents the area of the porch is A(x) = 8x² + 38x + 45. Option D is correct.
Learn more about the surface area here: https://brainly.com/question/2835293
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