SOLUTION: Determine the measure of angle B of triangle ABC given the following information: C = 120° a = 6 b = 2, and my options are: 25°, 46°, 14°
and 19°.
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-> SOLUTION: Determine the measure of angle B of triangle ABC given the following information: C = 120° a = 6 b = 2, and my options are: 25°, 46°, 14°
and 19°.
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Question 398510: Determine the measure of angle B of triangle ABC given the following information: C = 120° a = 6 b = 2, and my options are: 25°, 46°, 14°
and 19°.
We draw the triangle:
We extend BC, and draw a line segment from A perpendicular to the
extension of BC, intersecting it at D:
Angle ACD is 60° because it is supplementary to angle ACB which is 120°,
and 180°- 120° = 60°
Triangle ADC is a "30°60°90°" right triangle, and since its _
hypotenuse AC is 2, its lower leg CD is 1, and its vertical leg AD is √3.
BD = BC + CD = 6 + 1 = 7
Triangle ADB is a right triangle, therefore
tan(B) = =
Use inverse tangent function to get
Angle B = 13.89788625° closest to 14°.
Edwin