Question

Diketahui fungsi f(x)=3x+9.jika f(-2)=a dan f(b)=-6,nilai a+b adala

Answer 1

F(x) = 3x+9

f(-2) = 3(-2)+9 = -6+9 = 3

f(b) = 3b+9
-6 = 3b + 9
-6-9 = 3b
-15 = 3b
b = -15:3
b = -5

a+b = 3+(-5) = -2

Answer 2

F(-2) = 3(-2) + 9  = -6 + 9 = 3
berati a= 3
f(b) = -6
3b+9 = -6
    3b  = -6-9
     3b = -15
     b = -15/3= -5

a+b = 3+(-5)= -2