Answer:
10 squared units
Explanation:
This triangle is pretty easy since it creates a right triangle. So the base length and height length are pretty easy to identify.
The area of a triangle is .5*base*height.
The base length after drawing the points is a horizontal so just count it or do 4-0=4.
The height length after drawing the points is a vertical so just count it or do 4-(-1)=4+1=5.
So the area of the triangle is .5*4*5=.5(20)=10 units squared.
Now if you didn't fill like drawing it and you knew how to find the determinant.
You just compute
.5 times det| 0 -1 1 |
| 0 4 1 |
| 4 -1 1 |
.5[ 0 det| 4 1 | - -1 det| 0 1 | + 1 det | 0 4 | ]
| -1 1 | | 4 1 | | 4 -1 |
.5[ 0 - -1(0-4) + 1(0-16)]
.5[ 0 -4 -16]
.5[-20]
-10
And if you get a negative just take the absolute value of it giving you 10.