dengan cara ya,terimakasih :)

f(x) = ax +b
f(-2) = a(-2) + b
14 = -2a + b

f(x) = ax + b
f(3) = a(3) + b
-1 = 3a + b

-2a + b = 14
3a + b = -1
___________ -
-5a =15
a = 15 : -5
= -3

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

f(x) = ax + b
f (7) = -3x + 8
= -3(7) + 8
=-21 +8
=-13