Answer
$27\ in^2$
Work Step by Step
Find the area of the larger triangle and deduct the area of the smaller, unshaded triangle, to find the shaded area.
$A_1=\frac{1}{2}bh=\frac{1}{2}(10)(6)=(5)(6)=30$
$A_2=\frac{1}{2}bh=\frac{1}{2}(3)(2)=(1.5)(2)=3$
$A=A_1-A_2=30-3=27$