The midpoint of a segment can be found using the formulas fora directed line segment, x = ( a b ]X2 – x3) + xj and v=laf bjuz-yü +92. When using these formulas to find a midpoint, which is true?
O a= 1 and b = 2
O a = 2 and b= 1
O a= 1 and a + b = 2
O a= 2 and a + b = 2