Area of Shapes

 $A\ =\ bh$  

b = 8.6

h = 3

 $A\ =\ 8.6\left(3\right)$  

 $A\ =\ 25.8\ cm^2$  

A = bh

 $b\ =\ 2\ \frac{1}{4}$  

 $h\ =\ 1\ \frac{1}{2}$  

 $A\ =\ 2\ \frac{1}{4}\ \left(1\ \frac{1}{2}\right)$  

 $A\ =\ 3\ \frac{3}{8}\ ft^2$  

We know A and H, but not B.

Use:  $b\ =\ \frac{A}{h}$  

 $b\ =\ \frac{162}{18}$  

 $b=9m$  

 $A=bh$  

b = 12.2cm

h = 8cm, as it is perpendicular to the base.

 $A\ =\ 12.2\left(8\right)$  

 $A=97.6cm^2$  

Two triangles are formed when a parallelogram is cut in half

Therefore, the formula for the area of a triangle is:  $A\ =\ \frac{bh}{2}$  

The height of the triangle will form a right angle with the base. It is the perpendicular height.

Formula:  $A\ =\ \frac{b_1+b_2}{2}\ \cdot\ h$  

b1=12 ; b2=7 ; h=4

 $A=\frac{12+7}{2}\cdot4$  

 $A=\frac{19}{2}\cdot4$  

 $A=\frac{76}{2}$  

 $A=38in^2$