Question 1083265
shorter base = b = 3.5 inches
longer base = 3*b = 3*3.5 = 10.5
height = 2*(3*b) = 2*10.5 = 21


In summary so far,
shorter base = b1 = 3.5
longer base = b2 = 10.5
height = h = 21


Area of trapezoid
A = h*(b1+b2)/2
A = 21*(10.5+3.5)/2
A = 21*(14)/2
A = 294/2
A = 147


The area of the trapezoid is <font color=red>147 square inches</font>.