Question

Diketahui fungsi f(x) = ax + b , jika f(-2) = 5 dan f(3) = 15 maka nilai f(-5) + f(1) ?

Answer 1

F(x) = ax + b
f(-2) = a(-2) + b = 5
f(3) = a(3) + b = 15
•
-2a + b = 5
3a + b = 15
_________-
-5a = -10
a = -10/-5
a = 2

3a + b = 15
3.2 + b = 15
b = 15 - 6
b = 9

f(x) = 2x + 9

f(-5) + f(1)
(2.(-5) + 9) + (2.1 + 9)
-1 + 11 = 10