Alan Z. answered 08/30/24
Teaching and tutoring AutoCAD and Inventor for over 30 years.
Not an AutoCAD question, though you could find the answer by pacing a dimension override and using the input 20 - 4.49 - 2,79 - .79 the resulting dimension would give you your answer, or you could use the LINE tool and when ask the length type in that equation. Use the MEASAURE tool to measure the line to see the result.