What is the [tex]$y$[/tex]-coordinate of the point that divides the directed line segment from [tex]$J$[/tex] to [tex]$K$[/tex] into a ratio of [tex]$5:1$[/tex]?

A. [tex]$-8$[/tex]
B. [tex]$-5$[/tex]
C. [tex]$0$[/tex]
D. [tex]$6$[/tex]



Answer :

To find the [tex]$y$[/tex]-coordinate of the point that divides the directed line segment from point [tex]\( J \)[/tex] to point [tex]\( K \)[/tex] in the ratio [tex]\( 5:1 \)[/tex], we use the formula:

[tex]\[ v = \left( \frac{m}{m+n} \right) (v_2 - v_1) + v_1 \][/tex]

Let's denote:
- [tex]\( v_1 \)[/tex] as the [tex]$y$[/tex]-coordinate of point [tex]\( J \)[/tex]
- [tex]\( v_2 \)[/tex] as the [tex]$y$[/tex]-coordinate of point [tex]\( K \)[/tex]
- [tex]\( m \)[/tex] and [tex]\( n \)[/tex] as the parts of the ratio

Given:
- Coordinates of point [tex]\( J \)[/tex]: [tex]\( (x_1, 0) \)[/tex] so [tex]\( v_1 = 0 \)[/tex]
- Coordinates of point [tex]\( K \)[/tex]: [tex]\( (x_2, -6) \)[/tex] so [tex]\( v_2 = -6 \)[/tex]
- The ratio [tex]\( m:n = 5:1 \)[/tex] so [tex]\( m = 5 \)[/tex] and [tex]\( n = 1 \)[/tex]

Substitute these values into the formula:

[tex]\[ v = \left( \frac{5}{5+1} \right) (-6 - 0) + 0 \][/tex]

Now calculate the coefficients and the expression inside the parentheses:

[tex]\[ v = \left( \frac{5}{6} \right) (-6) \][/tex]

Next, perform the multiplication:

[tex]\[ v = \frac{5}{6} \times (-6) \][/tex]

Simplify the expression:

[tex]\[ v = -5 \][/tex]

Therefore, the [tex]$y$[/tex]-coordinate of the point that divides the line segment from [tex]\( J \)[/tex] to [tex]\( K \)[/tex] in the ratio of [tex]\( 5:1 \)[/tex] is:

[tex]\[ \boxed{-5} \][/tex]