f (x)=ax+b. jika f (-2)=14 dan f (3)=-1 maka nilai f (7)

jawab

f(x) =ax + b

f(-2) = 14 --> -2a + b = 14 ...(i)
f(3) = - 1 --> 3a + b = - 1 ....(ii)


(i dan ii) eliminasi

-2a + b = 14
3a + b = - 1 .....(-)
-5a = 15
a = - 3

-2a + b = 14
-2(-3) +  b = 14
 6  + b  =14
b = 8

f(x) = ax + b
f(x) = -3x + 8

f(7) = -3(7) + 8
f(7) = - 21 + 8
f(7) = -13

smoga membantush_! dan bermanfaat