It is
[tex]24x - 30[/tex]
The equation for area of a trapezoid is
[tex] \frac{1}{2} (a + b) \times h[/tex]
Substituting our values in
[tex] \frac{1}{2} (3x + 7 + 5x - 3) \times 6[/tex]
We can then simplify the expression
[tex] \frac{1}{2} (8x - 10) \times 6 \\ (4x - 5) \times 6 \\ 24x - 30[/tex]
