Question

Point m is the midpoint of kL. M(1,-1) and L(8,-7. What are the coordinates of point k?

Answer 1

Answer: (-6, 5)

Explanation:

Use the Midpoint Formula:
`((x_k, y_k)+(x_L,y_L))/(2)=(x_m, y_m)`

Separate the x's and y's and solve them individually:

`(x_k+x_L)/(2)=x_m\qquad \qquad \qquad \qquad(y_k+y_L)/(2)=y_m\\\\\\(x_k+8)/(2)=1\qquad \qquad \qquad \qquad \qquad (y_k-7)/(2)=-1\\\\\\x_k+8=2\qquad \qquad \qquad \qquad \qquad y_k-7=-2\\\\\\x_k\quad =-6 \qquad \qquad \qquad \qquad \qquad y_k\qquad =5`

So, the k-coordinate is (-6, 5)