PLEASE HELP A lamppost, CAB, bent at point A after a storm. The tip of the lamppost touched the ground at point C, as shown below: Triangle ABC has measure of angle C equal to 55 degrees, measure of angle ABC equal to 90 degrees, and length of BC equal to 20 What is the height, in feet, of the portion AB of the lamppost? A 20/tan 55 B 20 cos 55 C 20 tan 55 D 20/cos 55

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Explanation:

Check out the diagram below. This is what your textbook is likely showing, or similar to that.

We have a right triangle with angle C = 55. The horizontal portion is BC = 20. The height AB is h which is unknown for now

For the reference angle C = 55, the adjacent side (closest to the angle) is BC = 20 and the opposite side (furthest from the angle) is AB = h. Use the tangent rule to connect the two sides to form a ratio as shown below

tan(angle) = opposite/adjacent

tan(C) = AB/BC

tan(55) = h/20

20*tan(55) = h

h = 20*tan(55)

AB = 20*tan(55)

answer: option a.

step-by-step explanation:

you know that the quadrilateral opqr ( a four sided figure) is inscribed in circle. this means that all its vertices are on the circle.

then, by definition, the opposite angles of the quadrilateral are supplementary, this means that the sum of their measures is 180 degrees.

you can observe in the figure that the angles ∠opq   and the angle ∠orq   are opposite, therefore:

then, can be used to d to calculate the measure of ∠opq

in problems involving proportions, we can use cross products to test whether two ratios are equal and form a proportion. to find the cross products of a proportion, we multiply the outer terms, called the extremes, and the middle terms, called the means.

hope it