JAMB - Mathematics (2007 - No. 42)
What is the value of k if the mid-point of the line joining (1 - k, - 4) and (2, k + 1) is (-k , k)?
-3
-1
-4
-2
คำอธิบาย
(1-k+2) / 2 = - k and -4 + k + 1 = k
3-k = -2k and -3 + k = 2k
K = -3 and k = -3
3-k = -2k and -3 + k = 2k
K = -3 and k = -3