Section 3 - Topic 1 What is a Function? 1. A group of students were discussing whether the relationship on the graph is o function Ed: The relotionship is not a function because if I craw a horizontal line at y= 2, the horizon al line crosses the graph ot two points. Debra: The relationship is a function because it is a graph of two different Alejandro: The relationship is not a function because x = 1 has two different y-values. Antoine: The relationship is a function because I can write an equation for diline. Which students are not correct and whot is the flow in their argument:

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  Not correct: Ed, Debra, Antoine

Step-by-step explanation:

Ed is incorrect because he is using a horizontal line test instead of the appropriate vertical line test.

Debra is incorrect because the fact it is two different lines is irrelevant. A piecewise linear function may be two or more different lines.

Antoine is incorrect because the existence of an equation for the curve has nothing to do with whether or not it is a function. (Here, Antoine would need two equations with overlapping domains. The overlap of the domains is what tells you it is not a function.)

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Alejandro is correct. The relation fails the vertical line test

given : the shape of his satellite can be modeled by   where x and y are modeled in inches.

now,the given equation   is a equation of parabola.

here, coefficient of x is positive, hence the parabola opens rightwards.

on comparing this equation with standard equation , we get

in standard equation, coordinates of focus=(0,m)

thus for given equation coordinates of focus=(0,1.5)

step-by-step explanation: