Answer:
[tex]A=4x^5+16x^4+4x^3[/tex]
Step-by-step explanation:
The area of a trapezoid is found with the formula
[tex]A=\frac{(B+b)h}{2}[/tex]
where B is the measurement of the longest side of the trapezoid (the largest base) and b is the measurement of the shortest side of the trapezium (the minor base), and h is the height. In this case we have:
[tex]b=8x^2+3x\\B=2x^3-x\\h=4x^2[/tex]
so, substituting this values in the formula:
[tex]A=\frac{(2x^3-x+8x^2+3x)(4x^2)}{2}[/tex]
Simplifying the expression and joining like terms
[tex]A=\frac{(2x^3+8x^2+2x)(4x^2)}{2}[/tex]
Multiplying the numerator parentheses:
[tex]A=\frac{8x^5+32x^4+8x^3}{2}[/tex]
dividing by 2:
[tex]A=4x^5+16x^4+4x^3[/tex]
the simplified expression for the area of this trapezoid is
[tex]4x^5+16x^4+4x^3[/tex]