It's D, 3-2i.
Hope this helps
Here's some guidelines to help you:
For 1, 4, 5, and 6, they are 30-60-90 triangles. What's that you may ask? Well, it means that the sides have a predetermined length when one side is given. In #1 for example, you have a side of 11sqrt3, this means that "n" is 11 because in a 30-60-90 triangle, the longer side is the sqrt3 times the length of the shorter side. So to get the shorter side, we divide by sqrt3 to get 11. "m", or the hypotenuse, can be determined by taking twice the length of the shorter side. Since we figured out earlier that the shorter side is 11, 11 times 2 is 22. So the answer for #1 is n=11, m=22.
For 2 and 3, they are 45-45-90 triangles, triangles where the two lengths are the same and the hypotenuse is either leg length times sqrt2. In problem #2 for example, "y" must be 17 because one leg length is 17. "x", or the hypotenuse, is equal to 17sqrt(2) because 17 times sqrt(2).
You can apply all these rules to the other 4 problems I didn't explain.
Hope this long explanation clears your doubts!
Answer:
the mean is 4.2
Step-by-step explanation:
The bottom answer is correct. I had some trouble with this so I had to find x and y in separate parts.
TO FIND X
notice that the top triangle and bottom triangles are similar, meaning if you multiple all three sides of one by a specific number, it becomes the same size as the bottom triangle.
17 x n = 8, therefore n=8/17
8 x n = X, therefore X=64/17
For some reason, this does not give a correct value for Y, so I had to use trig
TO FIND Y
Notice that the angle DAB is the same as DBC (lets call this angle Ø)
Using trig rule, we know that the cos of an angle is equal to the adjacent side divided by the hypotenuses.
We can now form some equations:
cosØ = 15/17 (from the top triangle)
cosØ = 8/Y (from bottom triangle)
Now we know that Y=(8x17)/15 = 136/15
X=64/15 Y=136/15
