Question

If Q is the midpoint of PR, find the coordinates of R if P(l 1, -2) and Q(4, 3).

Answer 1

Explanation:

P(1, -2) ;Q(4,3)

Let R(x1,y1)

Midpoint=
`((x_(1)+x_(2))/(2),(y_1+y_2)/(2))\\` = (4,3)

`((1+x_1)/(2),(-2+y_1)/(2))=(4,3)\\`

Compare x coordinates and y coordinates

`(1+x_1)/(2)=4 ; (-2+y_2)/(2)=3`

1+x1 = 4*2 ; -2+y2 = 3*2

1+x1 = 8 ; -2 +y2 = 6

x1= 8-1 ; y2 = 6+2

x1 = 7 ; y2 = 8

R(7 , 8)