Suatu fungsi memiliki rumus f(x) = ax + b dengan nilai f(-2) = -1 dan f(1) = 11. Nilai 5a + b adalah?

f(x) = ax + b

f(-2) = -2a + b = -1
f(1) = a + b = 11

-2a + b = -1
a + b = 11
_________—
-3a = -12
a = 4

(4) + b = 11
b = 7

Jadi, nilai 5a + b = 5(4) + 7 = 27