The eqution of the diagonal of a parallelogram is 3y=5x +k. The two opposite vertices of a parallelogram are the points (1,-2), (-2,1).Find the value of k

Respuesta :

Answer:

[tex]k = 1[/tex]

Step-by-step explanation:

Given

[tex]3y = 5x + k[/tex]

Opposite points: [tex](1,-2)[/tex] and [tex](-2,1)[/tex]

Required

Find k

First, calculate the midpoint of the opposite points.

[tex](x,y) = 0.5(x_1 + x_2,y_1 + y_2)[/tex]

This gives:

[tex](x,y) = 0.5(1 -2,-2 + 1)[/tex]

[tex](x,y) = 0.5(-1,-1)[/tex]

Open bracket

[tex](x,y) = (-0.5,-0.5)[/tex]

The equation [tex]3y = 5x + k[/tex] becomes:

[tex]3 * -0.5 = 5 * -0.5 + k[/tex]

[tex]-1.5 = -2.5 + k[/tex]

Solve for k

[tex]k = 2.5-1.5[/tex]

[tex]k = 1[/tex]