031502
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Type the correct answer in each box. If necessary, use / for the fraction bar(s). Given: AB || CD . If the coordinates of point A are (8 , 0) and the coordinates of point B are (3 , 7), the y-intercept of AB is _____ . If the coordinates of point D are (5 , 5), the equation of line CD is y = ___ x + ___ .

Respuesta :

frika

Answer:

1. 11.2

2. -1.4

3. 12

Step-by-step explanation:

The equation of the line that passes through the points A(8,0) and B(3,7) is

[tex]\dfrac{x-8}{3-8}=\dfrac{y-0}{7-0},\\ \\y=-\dfrac{7}{5}(x-8).[/tex]

To find the y-intercept, plug into this equation x=0:

[tex]y=-\dfrac{7}{5}(0-8)=\dfrac{56}{5}=11.2.[/tex]

Two parallel lines have the same slope, so the equation of the line CD is

[tex]y=-\dfrac{7}{5}x+b.[/tex]

This line passes through the point D(5,5), thus

[tex]5=-\dfrac{7}{5}\cdot 5+b\Rightarrow b=5+7=12.[/tex]

Hence, the equation of CD is

[tex]y=-\dfrac{7}{5}x+12.[/tex]

Answer:

Im not sure about the other 2 but the last box is 12, the answer above is incorrect for PLATO. I just took the test.

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