How to find if it is a function or not: The set of ordered pairs (Z, A) where z is the zip code, and A is the street address.

It is not a function.

Step-by-step explanation:

A function is something that "eats" an input and transforms it into an output.

We write them as y = f(x)

Where x is the input, and y is the output.

Now, a function has an important rule, for each input x, the function can only "transform it" (or map it) into only one possible output.

This means that, for example, if we have, for x = x1.

And a single

f(x1) = y1

f(x1) = y2

where y1 and y2 are different values.

Then this is not a function, because it is mapping the value x1 into two different outputs.

In this case, we would have:

f(Z) = A.

So Z is the input, but we know that a ZIP code works for an entire city, and in a given city we have lots of different street addresses, then for a single value of the input, Z, we have a lot of possible values of the output.

This means taht the set (Z, A) can not represent a function.

second option

step-by-step explanation:

the measures of a triangle equal 180. use that to find x.

2x+3x+4x=180

9x=180

9x/9=180/9

x=20

now you know x, you know angle a is 40°, angle b is 60°, angle c is 80°.

because angle a is 40°, the first option doesn't work.

because angle b is 60°, the second option does work.

when you add angle a and b, you get 100°. complementary means it equals 90°, so the third option doesn't work.

when you add angle a and c, you get 120°, which is not 100.

first, you divide the triangle in two, tô form a retangle triangle. after, using pythagoream theorem:

18^2 = 14^2 + (x/2)^2

(x^2/4) + 196 = 324

x^2/4 = 324 - 196

x^2/4 = 128

x^2 = 512

x = √512

x = √2^9

x = 16√2 cm

i hope i you.