On a number line, the directed line segment from [tex]\( Q \)[/tex] to [tex]\( S \)[/tex] has endpoints [tex]\( Q \)[/tex] at -14 and [tex]\( S \)[/tex] at 2. Point [tex]\( R \)[/tex] partitions the directed line segment from [tex]\( Q \)[/tex] to [tex]\( S \)[/tex] in a [tex]\( 3:5 \)[/tex] ratio.

Which expression correctly uses the formula [tex]\(\left(\frac{m}{m+n}\right)\left(x_2-x_1\right)+x_1\)[/tex] to find the location of point [tex]\( R \)[/tex]?

A. [tex]\(\left(\frac{3}{3+5}\right)(2-(-14))+(-14)\)[/tex]

B. [tex]\(\left(\frac{3}{3+5}\right)(-14-2)+2\)[/tex]

C. [tex]\(\left(\frac{3}{3+5}\right)(2-14)+14\)[/tex]

D. [tex]\(\left(\frac{3}{3+5}\right)(-14-2)-2\)[/tex]



Answer :

To determine the location of point [tex]\(R\)[/tex] that partitions the directed line segment from [tex]\(Q\)[/tex] to [tex]\(S\)[/tex] in a [tex]\(3:5\)[/tex] ratio, we need to use the formula for the coordinate of a point that divides a segment in a given ratio.

Given:
- [tex]\(Q\)[/tex] is at [tex]\(-14\)[/tex] (let [tex]\(x_1 = -14\)[/tex])
- [tex]\(S\)[/tex] is at [tex]\(2\)[/tex] (let [tex]\(x_2 = 2\)[/tex])
- The ratio is [tex]\(3:5\)[/tex] (let [tex]\(m = 3\)[/tex] and [tex]\(n = 5\)[/tex])

The formula to find the location of point [tex]\(R\)[/tex] is:
[tex]\[ \left(\frac{m}{m+n}\right)(x_2 - x_1) + x_1 \][/tex]

Let's substitute these values into the formula:
[tex]\[ \left(\frac{3}{3+5}\right)(2 - (-14)) + (-14) \][/tex]

Now check the provided options:

1. [tex]\(\left(\frac{3}{3+5}\right)(2 - (-14)) + (-14)\)[/tex]
2. [tex]\(\left(\frac{3}{3+5}\right)(-14 - 2) + 2\)[/tex]
3. [tex]\(\left(\frac{3}{3+5}\right)(2 - 14) + 14\)[/tex]
4. [tex]\(\left(\frac{3}{3+5}\right)(-14 - 2) - 2\)[/tex]

Among these, the first option is:
[tex]\[ \left(\frac{3}{3+5}\right)(2 - (-14)) + (-14) \][/tex]

This matches the formula exactly with the given values. Therefore, the correct expression is:
[tex]\[ \left(\frac{3}{3+5}\right)(2 - (-14)) + (-14) \][/tex]

Solving this we get:
[tex]\[ \left(\frac{3}{8}\right)(16) - 14 \][/tex]
[tex]\[ 6 - 14 \][/tex]
[tex]\[ -8 \][/tex]

Thus the correct option is:
[tex]\[ \left(\frac{3}{3+5}\right)(2-(-14))+(-14) \][/tex]

And the location of point [tex]\(R\)[/tex] is [tex]\(-8\)[/tex].