G = {(1, 1), (1, 2), (1, 3), (1, 4)} Is G a function and why?

is not function. The reason is that it is not one-to-one.

Step-by-step explanation:

A function is a mapping that is also one-to-one.

is indeed a mapping; it takes an input and relates it to one or more outputs.

A mapping is one-to-one if and only if each input is mapped to only one output. is not one-to-one because it maps the input to four different outputs. Hence, isn't a function.

on your paper it doesn't say the answer but the the answer is altitude

step-by-step explanation:

∠1≅∠2 by the alternate exterior angles theorem.

step-by-step explanation:

given, a ∥ b and ∠1 ≅ ∠3 .we have to prove that e ∥ f

we know that ∠1≅∠3 and that a || b because they are given. we see that by the alternate exterior angles theorem. therefore, ∠2≅∠3 by the transitive property. so, we can conclude that e || f by the converse alternate exterior angles theorem.

we have to fill the missing statement.

transitivity property states that if a = b and b = c, then a = c.

now, given ∠1≅∠3 and by transitivity property ∠2≅∠3 .

hence, to apply transitivity property one angle must be common which is not in result after applying this property which is ∠1.

the only options in which ∠1 is present are ∠1 and ∠2, ∠1 and ∠4

∠1 and ∠4 is not possible ∵ after applying transitivity we didn't get ∠4.

hence, the missing statement is ∠1≅∠2.

so, ∠1≅∠2 by the alternate exterior angles theorem.