If a and B satisfy the absolute value of a + B-7 + (AB + Half) &# 178; = 0, find the value of 2 (a + b) + ab - (a + b) - 3AB

If a and B satisfy the absolute value of a + B-7 + (AB + Half) &# 178; = 0, find the value of 2 (a + b) + ab - (a + b) - 3AB

The absolute value of a + B-7 + (AB + Half) & # = 0
a+b-7=0
a+b=7
ab+1/2=0
ab=-1/2
2(a+b)+ab-(a+b)-3ab
=(a+b)-2ab
=7-2x(-1/2)
=7+1
=8