Suppose that the point A(x,y) belongs to this parabola. The defining point of the parabola is that the distance between a point F and the directrix. Suppose that the chosen point F is at (a,b). Then, the distance from A to the directrix is |b+4| while the distance from A to the focus is given by the pythagorean theorem:
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We have that these two have to be equal. Squaring both sides we get:
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This is the equation that describes all equations of parabolas with that directrix; you just need to choose the focus and substituting a and b will yield the equation.
Im not sure but i found the answer to be 19% full and 32.4 minutes to charge.
The one that does not show a direct variation is that answer B because I notice that letters A, C, and B have slopes and that the function is equal to kx, making it a direct variation. But on the answer B, the function y = 6/x is a indirect variation, making it equal to xy = 6.
Step-by-step explanation:
this is your answer..........