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40 votes
40 votes
What is the area of a triangle if the vertices are at

A(-11, 4)
B(-7, 8)
C(-4, 4)

What is the area of a triangle if the vertices are at A(-11, 4) B(-7, 8) C(-4, 4)-example-1
User Kumetix
by
2.8k points

1 Answer

15 votes
15 votes

Answer:

14 square units

Explanation:

You want the area of the triangle whose vertices are the points A(-11, 4), B(-7, 8), C(-4, 4).

Area formula

The area of a triangle is given by the formula ...

A = 1/2bh

where b is the base of the triangle, and h is the height, the1 perpendicular distance to the opposite vertex.

Dimensions

The diagram shows one side is the horizontal line AC. The length of that is the difference of the x-coordinates of the end points:

b = -4 -(-11) = 7

The opposite vertex, B, has a y-coordinate of 8, so the height of the triangle is ...

h = 8 -4 = 4

Application

We now have the information we need to use the area formula:

A = 1/2(7)(4) = 14 . . . . square units

The area of ∆ABC is 14 square units.

__

Additional comment

You can use the diagram and count grid squares to find the dimensions of the triangle.

User Nalina
by
2.5k points