number = x
Twice a number = 2x
Five less than twice a number = 2x-5
Three times the number = 3x
Difference of three times the number and 13 = 3x-13
One half the difference of three times the number and 13 = (1/2)(3x-13)
2x-5 = (1/2)(3x-13)
2x-5 = 3x/2-13/2
2x-5 = 3x/2-6.5
2x=3x/2-1.5
4x=3x-1.5
x=-1.5
Answer = -1.5
