<span>{(c,e),(c,d),(c,b)} is NOT a function since the input c has multiple outputs (e,d,b). So choice B is out
</span><span>{(b,b),(c,d),(d,c),(c,a)} is NOT a function either. The input 'c' corresponds to the output 'd' and 'a' at the same time. So choice C is out too
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Choices A and D are the answer. They are functions since any given input corresponds to exactly one output.
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For this problem you are going to need to know the point-slope equation which is:
y-y₁=m(x-x₁)
Now, m=slope and the x and y values are given to us already, so now we just plug our variables into the formula.
It should look like this:

Since all they are asking for is for you to put it into a formula this will be your answer.
Answer: A
Step-by-step explanation:
If you flip the second triangle straight upwards so that x is on top and z,y are on the bottom, you could visualize the points and angles in the same locations.
Answer:
f(-2) = -4x + 6
Step-by-step explanation:
f(x) = 2x + 6
f(-2) = -2(2x) + 6
f(-2) = -4x + 6