The cells in the grid each have length 1. What is the area enclosed by the geoboard quadrilateral below? Express your answer as a decimal rounded to the nearest tenth.

Guest Dec 17, 2018

#1**+2 **

We can use something known as "Pick'sTheorem" to answer this...

When the vertices of a figure have integer coordinates [ like this one]....the area is given by

(Number of integer coordinates on the boundary / 2 ) +( number of interior points with integer coordinates) - 1

Number of integer coordinates on the boundary = 5

Number of integer coordinates in the interior = 21

So....the area is

(5/2) + 21 - 1 =

2.5 + 20 =

22.5 units^2

CPhill Dec 17, 2018