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Ch. 4 - Laws of Sines and Cosines; Vectors
Blitzer - Trigonometry 3rd Edition
Blitzer3rd EditionTrigonometryISBN: 9780137316601당신이 사용하는 게 아니라요?교과서 변경
4장, 문제 46

In Exercises 45–46, find the area of the triangle with the given vertices. Round to the nearest square unit. (-2, -3), (-2, 2), (2, 1)

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Identify the coordinates of the vertices of the triangle: \(A(-2, -3)\), \(B(-2, 2)\), and \(C(2, 1)\).
Use the formula for the area of a triangle given coordinates \(A(x_1, y_1)\), \(B(x_2, y_2)\), and \(C(x_3, y_3)\): \(\text{Area} = \frac{1}{2} \left| x_1(y_2 - y_3) + x_2(y_3 - y_1) + x_3(y_1 - y_2) \right|\)
Substitute the coordinates into the formula: \(\text{Area} = \frac{1}{2} \left| (-2)(2 - 1) + (-2)(1 - (-3)) + 2((-3) - 2) \right|\)
Simplify the expression inside the absolute value by performing the operations inside the parentheses and then the multiplications.
Calculate the absolute value of the simplified expression, multiply by \(\frac{1}{2}\), and then round the result to the nearest whole number to find the area of the triangle.

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주요 개념

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