suatu fungsi dirumuskan f(x)=ax+b jika f(-2)=13 dan f(3)= -7,maka nilai f(-3)=... jelaskan dengan cara!

f(x) = ax + b
f(-2) = a(-2) + b
13 = -2a + b ...(1)

f(3) = 3a + b
-7 = 3a + b ...(2)

-2a + b = 13
3a + b = -7
__________ -
-5a = 20
a = -4

-2a + b = 13
-2(-4) + b = 13
b= 5

f(x) = -4x + 5
f(-3) = -4(-3) + 5
= 12 + 5
= 17