We are given two bases as 3 and 11
altitude is 8
formula for area of trapezoid is given by
[tex] A=\frac{a+b}{2} *h [/tex]
here a and b are two bases and h is height
plugging the given values we get
[tex] A=\frac{11+3}{2} *8 [/tex] =56
Area of trapezoid = 56 unit square