(1.)Find the slope of the line that passes through the given pair of points. (If an answer is undefined, enter UNDEFINED.) (?a + 3, b ? 3) and (a + 3, ?b) *******(2.)If the line passing through the points (a, 1) and (6, 5) is parallel to the line passing through the points (2, 7) and (a + 2, 1), what is the value of a?

Respuesta :

Answer:

1. The slope of the line is [tex]m=\frac{-2b+3}{2a}[/tex].

2. The value of a is 18.

Step-by-step explanation:

If a line passes through two points, then the slope of the line is

[tex]m=\frac{y_2-y_1}{x_2-x_1}[/tex]

(1)

It is given that the line passes through the points (-a + 3, b - 3) and (a + 3, -b). So, the slope of the line is

[tex]m=\frac{-b-(b-3)}{a+3-(-a+3)}[/tex]

[tex]m=\frac{-b-b+3}{a+3+a-3)}[/tex]

[tex]m=\frac{-2b+3}{2a}[/tex]

The slope of the line is [tex]m=\frac{-2b+3}{2a}[/tex].

(2)

If the line passing through the points (a, 1) and (6, 5), then the slope of the line is

[tex]m_1=\frac{5-1}{6-a}=\frac{4}{6-a}[/tex]

If the line passing through the points (2, 7) and (a + 2, 1), then the slope of the line is

[tex]m_2=\frac{1-7}{a+2-2}=\frac{-6}{a}[/tex]

The slopes of two parallel lines are same.

[tex]m_1=m_2[/tex]

[tex]\frac{4}{6-a}=\frac{-6}{a}[/tex]

On cross multiplication we get

[tex]4a=-6(6-a)[/tex]

[tex]4a=-36+6a[/tex]

[tex]4a-6a=-36[/tex]

[tex]-2a=-36[/tex]

Divide both sides by -2.

[tex]a=18[/tex]

Therefore the value of a is 18.