Please help me

Please help

there is only one way to arrange all the eight relative to each other because they are not distinct. we have

now there are nine places to place an (and not more than one in one place).   because we have four symbols, we need to choose four of these nine places to insert an . order does not matter because the are not distinct.

thus there are 1 · c(9,4) ways, or, if we calculate it,

thus there are 126 ways to form such "words."

the answer is c.) yes, [triangle]klp can be reflected across the line containing [line]kp and then translated so that p is mapped to m.

the reason is this:

looking at the triangles visually we can see they share the same features. using rigid transfromations we can reflect it over [line]kp then all we need to do is translate up.