dikeahui fungsi f(x)=ax+b.jika f(-5)=32 dan f(1)=-4,maka nilai dari f(7) adalah..?

Mapel : Matematika
Bab : Fungsi

f(x) = ax + b
f(-5) = -5a + b = 32
f(1) = a + b = -4
-------------------------   -
               -6a = 36
                  a = 36/-6
                  a = -6

a + b = -4
-6 + b = -4
b = -4 + 6
b = 2

f(x) = ax + b
f(7) = -4(7) + 2
f(7) = -28 + 2
f(7) = -26