Which set of ordered pairs represents a function?
a {(0, 1), (1, 3), (1, 5), (2, 6)}
b {(0, 0), (1, 2), (2, 4), (3, 4)}
c {(0, 1), (1, 2), (2, 3), (2, 4)}
d {(0, 0), (0, 2), (2, 2), (2, 4)}

Step-by-step explanation:

First of all, we have to remember what's a function.

A function is actually a relation between two sets, where to every element of the first set (domain) is assigned ONLY ONE element of the second set (range).

If the relation assigns more than one range element to a domain element, such relation won't be a function.

So, in this case, we just have to see which set of ordered pairs is really a function.

You can observe that choice B.  {(0, 0), (1, 2), (2, 4), (3, 4)}, represents a function, because to every domain element there's assigned only one range element. For x=0, there's y=0, x=1 with y=2, x=2 with y=4 and x=3 with y=4.

Therefore, the answer is B.

x = -4

step-by-step explanation:

- 20 - 4(x + 3) = 4x

=> -20 - 4x - 12 = 4x

=> - 32 -4x = 4x

=> -32 = 4x + 4x

=> - 32 = 8x

=> -32/8 = x

=> -4 = x