Let L represent the ladder length, and x the distance the horiz. ladder reaches out from the wall. Then L = x + 3, where x is the distance of the bottom of the ladder from the wall when the top of the ladder is 9 ft. above the ground.
Consider the triangle formed by the hypotenuse (L, same as ladder length), the (vertical) side opposite the angle formed by the hypo. (with length 9 ft) and the horiz side (which we will call x). Then, according to the Pythagorean Theorem,
L^2 = x^2 + 9^2. But L = x + 3, and L^2 = x^2 + 6x + 9 = x^2 + 9^2. Solving this equation results in x=3. 6x + 9 = 9^2, or
6x + 9 = 81
6x = 72
x = 12
But L = x+3. So L=12+3, or L = 15 (feet).
9514 1404 393
Answer:
KK KL KM KN KP LL LM LN LP MM MN MP NN NP PP
Step-by-step explanation:
Instead of starting with adjacent letters in the list, we start with the same letter. There are 15 possible pairs.
KK KL KM KN KP LL LM LN LP MM MN MP NN NP PP
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<em>Additional comment</em>
We leave out pairs with letters previous, because you've said KL is the same as LK, and KL has already been listed. The problem with this list is that it misstates the probabilities of randomly obtaining a given pair. It is not 1/15, but is 2/25 for all but letter duplicates. For duplicates (KK), the probability is 1/25, not 1/15.
4/3
Remember if two lines are perpendicular, the product of their slopes are -1
N/3 if thats what your looking for
