Question

P is the midpoint of line segment A(2,1)and B(5,-8) .P lies on the line 2x-y+k=0, find a

Answer 1

Answer:

Step-by-step explanation:

2x-y+k=0

2x +k =y

Slope m = 2

P = ((x1+x2)/2 , (y1+y2)/2)

  = ((2+5)/2 , (1-8)/2))

  = (7/2 , -7/2)

m = 2

y - y1 = m(x-x1)

y + 7/2 = 2( x-7/2)

(2y+7)/2 = 2( (2x-7)/2)

2y +7 = 2(2x-7)

2y +7 = 4x-14

4x -2y - 21 = 0

2x - y -21/2 =0

therefore k = -21/2