198k views
17 votes
100Pts fast plz

A triangular pen is modeled by △ABC. The vertices of △ABC are A(0, 8), B(12, 3), and C(7, –9). What is the area of the pen?

User Kathia
by
8.1k points

1 Answer

4 votes

Answer:

The area of the triangle is 84.511 square units.

Explanation:

First step, we need to calculate lengths of line segments AB, BC and AC by Pythagorean Theorem:

AB:


AB = \sqrt{(12-0)^(2)+(3-8)^(2)}


AB = 13

BC:


BC = \sqrt{(7-12)^(2)+(-9-3)^(2)}


BC = 13

AC:


AC = \sqrt{(7-0)^(2)+(-9-8)^(2)}


AC \approx 18.385

Now, we can determine the area of the triangle (
A) by Heron's formula:


A = √(s\cdot (s-AB)\cdot (s-BC)\cdot (s-AC)) (1)


s = (AB+BC+AC)/(2) (2)

Where
s is the semiperimeter of the triangle.

If we know that
AB = 13,
BC = 13 and
AC \approx 18.385, then the area of the triangle is:


s = 22.193


A = 84.511

The area of the triangle is 84.511 square units.

User Kasim Rangwala
by
9.0k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories