CF = CD + DF (since D is simply a point on the line, and C to that point added onto F to that point is CF), so 4y-9+2y-7=14. Adding it up, we get 6y-16=14 and adding by 16 we get 30=6y. Dividing both sides by 6, we get y=5. Plugging that into DF, we get 10-7=DF=3
notice, if the original area was πr², then the new area has a factor in front of it, that much.
Answer:−x2−6xy+8y2+9yz−12
(x + y = 29)
(y = 29 - x)
(5x + 2(29 - x) = 100)
(5x + 58 - 2x = 100)
(3x = 42)
(x = 14)
(y = 15)
(14 5-point questions and 15 2-point questions)