Given a + B = 4, A-B = - 3, find the value of negative half a & # 178; + Half B & # 178

Given a + B = 4, A-B = - 3, find the value of negative half a & # 178; + Half B & # 178

Square difference formula (a + b) (a-b) = A & # 178; - B & # 178; = 4 × (- 3) = - 12
So - A & # 178 / 2 + B & # 178 / 2 = - (A & # 178; - B & # 178;) / 2 = 12 / 2 = 6