Question

Diketahui f(x)=ax-b,dengan f(-3)=5 dan f(1/2)=-9,Tunis fungsinya adala?

Answer 1

F(x) = ax - b
f(-3) = 5 maka - 3a - b = 5
f(1/2) = - 9 maka - a/2 - b = - 9 atau - a - 2b = - 18
eliminasi:
- 6a - 2b = 10
- a - 2b = - 18
___________ - 
- 5a = 28
   a = - 28/5
   28/5 - 2b = - 18
2b = 28/5 + 18
2b = 118/5
b = 59/5

rumus fungsi:
f(x) = (-28/5)x + 59/5

Answer 2

F(x) = ax-b
f(-3) = 5
-3a-b = 5 --->b = -3a-5
f(1/2) = -9
1/2a-b = -9
1/2a-(-3a-5) = -9
1/2a+3a+5 = -9
7/2a = -9-5
7/2a = -14
a = -14*2/7
a = -4
b = -3a-5
b = -3(-4)-5
b = 12-5
b = 7

f(x) = ax-b
f(x) = -4x-7