13-11 9/20 = 1 11/20 sooo G
Try dividing both sides by 2.
Hope i helped :)
(It's kinda cool, because by dividing both sides by 2 we get !<3u :)
Complete question :
The latter is leaning against the building so that the distance from the ground to the top of the ladder is 9 feet less than the length of the ladder finally put the ladder in the distance from the bottom of the ladder to the building 15 feet. Find length of the ladder.
Answer:
17
Step-by-step explanation:
From Pythagoras :
Hypotenus = sqrt(opposite² + adjacent²)
From the diagram
l = sqrt((l-9)² + 15²)
l² = (l² - 18x + 81 + 225)
Square both sides
l² = l² - 18x + 306
l² - l² = 306 - 18x
18l = 306
l = 306/18
l = 17
First we find the mean (average)
(7 + 8 + 9 + 9 + 10 + 11)/6 = 54/6 = 9
now we subtract the mean from every data number....and square it
7 - 9 = -2...-2^2 = 4
8 - 9 = -1...-1^2 = 1
9 - 9 = 0....0^2 = 0
9 - 9 = 0...0^2 = 0
10 - 9 = 1....1^2 = 1
11 - 9 = 2....2^2 = 4
now we find the mean (average) for those numbers
(4 + 1 + 0 + 0 + 1 + 4) / 6 = 10/6 = 1.67...this is the variance
to find the standard deviation, take the sqrt of the variance
sqrt 1.67 = 1.29 <== ur answer
