Leonardo draws the obtuse triangle pictured here and calculates the area in square units. What is the area of Leonardo’s triangle? (1 point) Leonardo’s triangle has an area of blank square units.

The coordinates of the triangle are
C: (3, 2)
A: (-5, -4)
And B: (3, -3)

1 answer

To find the area of triangle \( C \), \( A \), and \( B \) with the coordinates given:

  • \( C(3, 2) \)
  • \( A(-5, -4) \)
  • \( B(3, -3) \)

We can use the formula for the area of a triangle determined by three points \((x_1, y_1)\), \((x_2, y_2)\), and \((x_3, y_3)\):

\[ \text{Area} = \frac{1}{2} \left| x_1(y_2 - y_3) + x_2(y_3 - y_1) + x_3(y_1 - y_2) \right| \]

Substituting the coordinates into this formula:

Let

  • \((x_1, y_1) = (3, 2) , (C)\)
  • \((x_2, y_2) = (-5, -4) , (A)\)
  • \((x_3, y_3) = (3, -3) , (B)\)

Now, substitute these values into the area formula:

\[ \text{Area} = \frac{1}{2} \left| 3(-4 - (-3)) + (-5)(-3 - 2) + 3(2 - (-4)) \right| \]

Calculating each term inside the absolute value:

  1. \( 3(-4 + 3) = 3(-1) = -3 \)
  2. \( -5(-3 - 2) = -5(-5) = 25 \)
  3. \( 3(2 + 4) = 3 \times 6 = 18 \)

Now substitute these results back into the formula:

\[ \text{Area} = \frac{1}{2} \left| -3 + 25 + 18 \right| \]

Combine the values inside the absolute value:

\[ -3 + 25 + 18 = 40 \]

Then we compute the area:

\[ \text{Area} = \frac{1}{2} \left| 40 \right| = \frac{1}{2} \times 40 = 20 \]

Thus, the area of Leonardo’s triangle is

\[ \boxed{20} \text{ square units.} \]