To find the area of a rectangle, you multiply the lengths of two of its sides together. Given that the sides of the rectangle have lengths of (3x+10) units and (5x-11) units respectively, we can find the area by multiplying these two expressions together.
Hence, the area of the rectangle can be found using the equation:
Area = (3x + 10) * (5x - 11)
So, the expression that represents the area of the rectangle is (3x + 10)(5x - 11).