K is the midpoint of HJ, HK = x + 6, and HJ = 4x - 6, then KJ =
HJ is a line segment. Options are
a. 15
b. 9
c. 4
d. 10
HJ = 4x - 6
HK = x + 6
KJ = HJ - HK = (4x - 6) - (x + 6) = 3x - 12
However, the problem states that K is the midpoint, which means that
KJ = HK, therefore, (3x - 12) = (x + 6)
3x - 12 = x + 6
3x - x = 6 + 12
2x = 18
x = 9
The answer is b. 9
HJ = 4x - 6 = 4(9) - 6 = 30
HK = x + 6 = 9 + 6 = 15
KJ = 3x - 12 = 3(9) - 12 = 27 - 12 = 15