On a number line, the directed line segment from Q to S has endpoints Q at –8 and S at 12. Point R partitions the directed line segment from Q to S in a 4:1 ratio. Which expression correctly uses the formula (StartFraction m Over m n EndFraction) (x 2 minus x 1) x 1 to find the location of point R? (StartFraction 1 Over 1 4 EndFraction) (12 minus (negative 8)) (negative 8) (StartFraction 4 Over 4 1 EndFraction) (12 minus (negative 8)) (negative 8) (StartFraction 4 Over 4 1 EndFraction) (negative 8 minus 12) 12 (StartFraction 4 Over 1 4 EndFraction) (negative 8 minus 12) 12