Question

Find the area of the shaded region in the figure below.

Answer 1

Area of rectangle=> L•l= 8•5= 40 in²
Area of the triangle=> (b•h)/2= (8•3)/2= 24/2= 12 in²

Area of the shadowed surface is 40-12= 28 in²

Answer 2

The formula of an area of a triangle:

$A_{\triangle}=\dfrac{1}{2}bh$

b - base

h - height

We have b = 8in and h = 3in. Substitute:

$A_{\triangle}=\dfrac{1}{2}(8)(3)=(4)(3)=12\ in^2$

The formula of an area of a rectangle:

$A_{\boxed{\ }}=lw$

l - length

w - width

We have l = 8in and w = 5in. Substitute:

$A_{\boxed{\ }}=(8)(5)=40\ in^2$

The area of a shaded region:

$A=A_{\boxed{\ }}-A_{\triangle}\\\\A=40\ in^2-12\ in^2=28\ in^2$

Answer: 28 in²