You can split the shape into two pieces; a triangle and a trapezoid.
The triangle is base times height divided by two, or 8 * 5.75 / 2, which equals 23.
The trapezoid is( base 1 + base 2 )/ 2 * height, or ( 8 + 4 ) / 2 * 2, which equals 12.
So the area is 35 square cm.
