The following figure shows \triangle ABC△ABCtriangle, A, B, C with side lengths to the nearest tenth. Triangle ABC. Side AC measures 8 units and side BC measures 15 units. Angle B is 28 degrees. Triangle ABC. Side AC measures 8 units and side BC measures 15 units. Angle B is 28 degrees. Find m\angle Am∠Am, angle, A. Note that m\angle Am∠Am, angle, A is acute. Round to the nearest degree.

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Answer:

62

Step-by-step explanation:

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The measurement of the angle A for the considered triangle is found being of 62° approximately.

What is law of sines?

For any triangle ABC, with side measures |BC| = a. |AC| = b. |AB| = c,

we have, by law of sines,

[tex]\dfrac{sin\angle A}{a} = \dfrac{sin\angle B}{b} = \dfrac{sin\angle C}{c}[/tex]

Remember that we took

[tex]\dfrac{\sin(angle)}{\text{length of the side opposite to that angle}}[/tex]

For the considered triangle, we can use sine rule.

In triangle ABC, we're given that:

  • |AC| = 8 units
  • |BC| = 15 units
  • m∠B = 28°
  • m∠A = ?° (to be found)

The side opposite to angle A is BC and the side opposite to angle B is AC. Thus, by sine law, we get:

[tex]\dfrac{\sin(m\angle A)}{|BC|} = \dfrac{sin(m\angle B)}{|AC|}\\\\\dfrac{\sin(m\angle A)}{15} = \dfrac{\sin(28^\circ)}{8}\\\\\sin(m\angle A ) \approx \dfrac{15 \times 0.46947}{8} \approx 0.88026\\\\m\angle A \approx \sin^{-1}(0.88026)\\\\m\angle A \approx 61.67^\circ, 118.32^\circ[/tex]

But since angle A is acute(angle with measure of less than 90 degrees), thus, m∠A ≈ 61.67° ≈ 62°

Thus, the measurement of the angle A for the considered triangle is found being of 62° approximately.

Learn more about law of sines here:
https://brainly.com/question/17289163