Final answer:
The residual for Patient 9's systolic blood pressure is calculated by subtracting the standard value (120 mm Hg) from the observed value (158 mm Hg), resulting in a residual of 38 mm Hg.
Step-by-step explanation:
To calculate the residual for Patient 9's systolic blood pressure, first, we need to determine what the expected or standard systolic blood pressure value is. According to new guidelines from the American College of Cardiology and American Heart Association, normal blood pressure is less than 120/80 mm Hg. From the table provided, the categories for systolic blood pressure are 90-119 mm Hg for normal, 120-139 mm Hg for elevated, and 140 mm Hg or higher as hypertension. Since the typical blood pressure of a young adult is 120 mm at systolic, we will use this value as our standard for calculating the residual.
Patient 9's actual systolic blood pressure is 158 mm Hg. The residual is the difference between the observed value and the standard value. Therefore, the residual is 158 mm Hg (observed) - 120 mm Hg (standard) = 38 mm Hg.