Triangle With Vertices

by Larry Rieck
(Canada)

Question

Find the area of the triangle with vertices (-1,4), (-1,8), and (3,4)

Answer

STEP 1
Once you plot out the coordinates given, this triangle is revealed to be a right-angle triangle. We can thus apply the formula of calculating the area of a right-angle triangle:

A = (b x h)/2

A = Area, b = base, h = height.

STEP 2
From the coordinates, we can calculate the height and base of the triangle:

b = 3 - (-1)
b = 4

h = 8 - 4
h = 4

STEP 3
Now then, we can replace the variables with the information we have:

A = (b x h)/2
A = (4 x 4)/2
A = 16/2
A = 8

Therefore, the area of this triangle is 8 square units. Always keep in mind to use the correct unit of measurement in your answers!

You can also refer to our page on Area of a Triangle for a video tutorial.

If you like what we're doing, please visit our new platform, Zap Zap Math, for something new and exciting coming your way!