Answer:
2.2
Step-by-step explanation:
If we let y represent the value of interest then the requirement for P tells us ...
... (y -1)/(5 -y) = 3/7
We can multiply by 7(5-y) to get
... 7(y -1) = 3(5 -y)
... 7y -7 = 15 -3y . . . . . eliminate parentheses
... 10y = 22 . . . . . . . . . add 3y+7, then divide by the coefficient of y to get ...
... y = 2.2 . . . . . the y-coordinate for P