tolong di bantu dengan cara kerjanya yah kk.. no 11 dan 12

11) f(x) = (2x - 3) / (x + 5)
y = (2x - 3) / (x + 5)
y (x + 5) = (2x - 3)
yx + 5y = 2x - 3
yx - 2x = -5y - 3
x (y - 2) = -5y - 3
x = (-5y - 3) / (y - 2)
f(x)-¹= (-5x - 3) / (x - 2)
atau
f(x) -¹ = - (5x + 3) / - (2 - x)
f(x)-¹ = (5x + 3) / (2 -x)

12) f(x) = ax + b
f(2) = a(2) + b = 0
= 2a + b = 0 .........(1)
f(-3) = a(-3) + b = 10
= -3a + b = 10 .......(2)
eliminasi (1) dan (2)
2a + b = 0
-3a + b = 10
_________-
5a = -10
a = -2
masukan nilai a = -2 ke persamaan (1)
2a + b = 0
2(-2) + b =0
b = 4
maka fungsinya f(x) = -2x + 4
nilai a + b = -2 + 4 = 2