In the figure below, a pole hast two wires attached to it, one on each side, forming two right triangles. -How tall is the pole? -How far from the base of the pole does Wire 2 attach to the ground? -How long is Wire 1?
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The side adjacent to the 41° angle is 38ft. The pole is on the opposite side to the 41° angle, so you can use \[\tan\theta = \frac{\text{opposite}}{\text{adjacent}}\] \[\tan41^\circ = \frac{\text{height}}{38\text{ ft}}\] The distance from where wire 2 meets the ground to the base of the pole is the opposite side to the 38° angle, and the pole is the adjacent side \[\tan38^\circ = \frac{\text{distance from base}}{\text{height}}\] The length of wire 1 can be worked out 3 ways: using \[\sin\theta = \frac{\text{hypotenuse}}{\text{opposite}}\] \[\sin41^\circ = \frac{\text{length}}{\text{height}}\] using \[\cos\theta = \frac{\text{hypotenuse}}{\text{adjacent}}\] \[\cos41^\circ = \frac{\text{length}}{38\text{ ft}}\] or using \[\text{hypotenuse} = \sqrt{(38\text{ ft})^2 + (\text{height})^2}\]
Thanks I knew I had to use tan I just needed better explanation on how to use it. I did this problem in class but the teacher is not so good ate explaining. THANKS!
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