The problem of positive proportion function and inverse proportion function Given that y = Y1 + Y2, Y1 is inversely proportional to χ. When χ = 1, y = 4; when χ = 2, y is equal to 5. Find the value of Y (process) when χ = 4

The problem of positive proportion function and inverse proportion function Given that y = Y1 + Y2, Y1 is inversely proportional to χ. When χ = 1, y = 4; when χ = 2, y is equal to 5. Find the value of Y (process) when χ = 4

Let Y1 = KX
Then y = KX + Y2, the known conditions can be substituted into the equations
4=k+y2
5=2k+y2
By solving this system of linear equations of two variables, we can get: k = 1, y2 = 3
That is y = x + 3
Substituting x = 4 gives y = 7