Tolong ya 8 9 dan 10 nya

8 . f(x) = ax+b

f(-2) = 14
(3) = -1


a(-2)+b = 14
a(3)+b = -1

-2a+b = 14
3a +b = -1
-------------- -
-5a = 15
a = -5


3a +b = -1
3(-5) + b = -1
-15 +b = -1
b = -1 + 15
b = 14


jadi
f(x) ax+b
f(x) = -5a + 14

untuk f(4)
f(x) = -5(4) + 14
= -20 +14
= -6


9.
8/x^2-2x-3 = 2/x+1

8/(x-3)(x+1) + 2/(x+1)


samakan penyebut jadi (x-3)(x+1)

8/(×-3)(x+1) + 2/(x-3)(x+1)


8+ 2(x-3)
--------------
(x-3)(x+1)


8+ 2x -6
------------
(x-3)(x+1)

2+2x
-------------
(x-3)(-x+1)


10.
1,5 - (2+ (5/4))
-------------
(5/6 -5/3)

selesaikan yang atas dl

samkan penyebutnya


1,5 - ( 8-5 /4)
-----------
(5-10/6)
1,5 - (3/4)
------
-5/6

1,5 - (3/4 . -6/5)

1,5 - ( -18/20)

15/10 + 18/20


samakan penyebut


30+ 18
---------
20

= 48/20.
= 12/5