Answer:
The area of the triangle is:

Explanation:
Recall that the area of any triangle is defined as the product of the triangle's base times the triangle's height, divided by two:

therefore, in our case, notice that the length of the triangle's base is 4 units (from x = 0 to x = 4), and the triangle's height is also 4 units (from y = -5 to y = -1)
Then the triangle's area becomes:
