Calculating Permutations Try it
A teacher has four books—A, B, C, and D—to assign to four students in any order he prefers.
Set S includes all possible arrangements of the four books.
Set X includes all possible arrangements when book C is chosen first and D is chosen second.
Which notation is correct?
If book C is chosen first and D is chosen second, in how many ways can the teacher assign the books?

the aswere is the one with all 8's and the second one is with the 10,8 and 6

step-by-step explanation:

answer: a

step-by-step explanation: the answer is a due to the rule of symmetry; that a line of symmetry must divide a figure into 2 pieces that are the exact same, only reflected over a line of symmetry. b and c do not have lines of symmetry and would not divide the figure evenly, thus making the answer a.

isocolese triangle

we know that the line connect a and b is the hyptonuse

so first find the hypotonuse length using the distance formula, call the length c

since it is an isocolese triangle, the lengths of the legs are the same

using pythagorean theorem,

in this case, a=b since isocolese triangle so we get

or

we can find c so we can find the distances

we know that if we draw 2 circles, each has center at a and b, and find where they intersect, we can the 2 possible locations for c

if a has center at (xa,ya) and b has center at (xb,yb), then we can solve where

and

intersect to find where they intersect

i'm not going to put an example because i have to go to class. i hope this explanation is enough

isn't it a pentagon? sense [3 (triangle) + 4 (rectangle)] - 2 (triangle and rectangle connected) = 5 (pentagon)