Point P divides the directed segment from A to B in the ratio 9 to 2. The coordinates of point A are
(-4,-2) and the coordinates of point P are (2, 1). Find the coordinates of point B. Round your answer to
the nearest tenth if necessary.

Respuesta :

Answer:

[tex]B =(3.3,1.7)[/tex]

Step-by-step explanation:

Given

[tex]A(x_1,y_1) = (-4,-2)[/tex]

[tex]P(x,y) = (2,1)[/tex]

[tex]m : n = 9 : 2[/tex]

Required

The coordinates of [tex]B(x_2,y_2)[/tex]

The line segment from ratio is calculated as:

[tex](x,y) = (\frac{mx_2 + nx_1}{m+n},\frac{my_2 + ny_1}{m+n})[/tex]

Substitute: A, P, m and n

[tex](2,1) = (\frac{9 * x_2 + 2*-4}{9+2},\frac{9*y_2 +2 *-2}{9+2})[/tex]

[tex](2,1) = (\frac{9x_2 -8}{11},\frac{9y_2 -4}{11})[/tex]

Multiply through by 11

[tex](22,11) = (9x_2 -8,9y_2 -4)[/tex]

By comparison:

[tex]9x_2 - 8 = 22[/tex]

[tex]9y_2 - 4 = 11[/tex]

So, we have:

[tex]9x_2 - 8 = 22[/tex]

[tex]9x_2 = 22 +8[/tex]

[tex]9x_2 = 30[/tex]

Solve for x2

[tex]x_2 = 30/9[/tex]

[tex]x_2 = 3.3[/tex]

[tex]9y_2 - 4 = 11[/tex]

[tex]9y_2 = 11+4[/tex]

[tex]9y_2 = 15[/tex]

Solve for y2

[tex]y_2 =15/9[/tex]

[tex]y_2 =1.7[/tex]

So, the coordinates of B is:

[tex]B =(3.3,1.7)[/tex]